AMBON, Indonesia — He was too sick to eat, and Min Min Chan's chest ached with each breath he sucked. It didn't matter: The Thai captain warned him to get back on deck and start hauling fish onto the trawler or be tossed overboard. As a 17-year-old slave stuck in the middle of the sea, he knew no one would come looking if he simply vanished.

Less than a month earlier, Chan had left Myanmar for neighboring Thailand, looking for work. Instead, he said a broker tricked and sold him onto the fishing boat for $616. He ended up far away in Indonesian waters before even realizing what was happening.

Tens of thousands of invisible migrants like Chan stream into Thailand, Southeast Asia's second-largest economy, every year. Many are used as forced labor in various industries, especially on long-haul fishing boats that catch seafood eaten in the U.S. and around the world. Others are dragged into the country's booming sex industry. Ethnic Rohingya asylum seekers from neighboring Myanmar are also held for ransom in abysmal jungle camps.

Next week, when a U.S. report on human trafficking comes out, Thailand may be punished for allowing that exploitation. The country has been on a U.S. State Department human trafficking watch list for the past four years. Washington warned in last year's report that without major improvements, it would be dropped to the lowest rung, Tier 3, joining the ranks of North Korea, Syria, Iran and Zimbabwe.

Though Thailand says it is trying to prevent such abuses and punish traffickers, its authorities have been part of the problem. The U.S. has said the involvement of corrupt officials appears to be widespread, from protecting brothels and workplaces to cooperating directly with traffickers.

A downgrade could lead the U.S. to pull back certain forms of foreign support and exchange programs as well as oppose assistance from international financial institutions such as the World Bank. Washington has already cut some assistance to Bangkok following last month's Thai military coup.

Thailand is paying a U.S. public relations company $51,000 a month to help in its push for better standing. The government issued a progress report for 2013, noting that investigations, prosecutions and the budget for anti-trafficking work all are on the rise.

"We recognize that it's a very serious, very significant problem, and we've been building a legal and bureaucratic framework to try to address these issues," said Vijavat Isarabhakdi, Thailand's ambassador to the U.S. "We feel that we have turned a corner and are making great progress in this area."

At least 38 Thai police were punished last year or are being investigated for alleged involvement in trafficking, but none has stood trial yet. Four companies have been fined, and criminal charges against five others are pending. But the government pulled the licenses of only two of the country's numerous labor recruitment agencies.

In Geneva on Wednesday, Thailand was the only government in the world to vote against a new U.N. international treaty that combats forced labor by, among other things, strengthening victims' access to compensation. Several countries abstained.

"Thailand tries to portray itself as the victim while, at the same time, it's busy taking advantage of everybody it can who's coming through the country," said Phil Robertson, deputy director of Human Rights Watch's Asia division. "The exploitation of migrants, the trafficking, it comes through Thailand because people know they can pay people in the government and in the police to look the other way."

____

Chan's story is a common nightmare. A recruiter showed up in his village in Myanmar, also known as Burma, offering good money to work on a fishing boat in Thailand. Chan said after sneaking across the border by foot, he was sold onto a boat by the broker and told to hide inside to avoid being seen by Thai authorities.

"'You have to work at least six months. After that, you can go back home,'" Chan said the captain told him. "I decided, 'I can work for six months on this boat.'"

But after the ship docked 17 days later on eastern Indonesia's Ambon island, Chan met other Burmese workers who told a very different story: There was no six-month contract and no escape. Now thousands of miles from home, he realized he no longer owned his life — it had become a debt that must be paid.

Ambon, in the Banda Sea, is peppered with churches and pristine dive sites. At the port, deep-sea fishermen in tattered T-shirts and rubber boots form human chains on boats, tossing bag after bag of frozen snapper and other fish into pickup trucks bound for cold storage. Much of it will later be shipped to Thailand for export.

They speak Burmese, Thai and other languages. Their skin is dark from the sun, and some faces look far older than their ropey bodies.

On the cramped boat, Chan said he slept only about three hours a night alongside 17 other men, mostly Burmese, sometimes working on just one meal of rice and fish a day. There was no fresh water for drinking or bathing, only boiled sea water with a briny taste.

In his first month at sea, he got sick and didn't eat for three days. He was sleeping when the captain threatened him.

"Why are you not working? Why are you taking a rest?" Chan recalled him saying. "Do we have to throw you off into the water?"

Some of Chan's friends carried him onto the deck, where he was given medicine before getting back to work.

For the next year, he labored, hauling up thousands of kilograms (pounds) of fish as he tried to shake a stubborn cough. He saw land every couple of months, but there was no way to leave the port.

He said he was given occasional packs of cigarettes, noodles and coffee, but he never got paid.

___

Thailand shipped some $7 billion worth of seafood abroad last year, making it the world's third-largest exporter. Most went to Japan and the U.S., where it ranks as the No. 3 foreign supplier.

The United Nations estimates the industry employs 2 million people, but it still faces a massive worker shortage. Many Thais are unwilling to take the low-paid, dangerous jobs that can require fishermen to be at sea for months or even years at a time.

An estimated 200,000 migrants, mostly from neighboring Myanmar and Cambodia, are laboring on Thai boats, according to the Bangkok-based nonprofit Raks Thai Foundation. Some go voluntarily, but a U.N. survey last year of nearly 600 workers in the fishing industry found that almost none had a signed contract, and about 40 percent had wages cut without explanation. Children were also found on board.

Forced or coerced work is more common in certain sectors, including deep-sea fishing and seafood processing plants where some workers have reported being drugged and kidnapped.

Long-haul fishermen like Chan have it the worst. They are worked around the clock seven days a week with very little food and often no clean water. They risk getting fouled in lines, being swept overboard during storms or losing fingers cleaning fish.

But often the biggest threat is their captain. A 2009 U.N. report found that about six out of 10 migrant workers on Thai fishing boats reported seeing a co-worker killed. Chan faced abuse himself and saw one sick Burmese fisherman die. The captain simply dumped the body overboard.

Thailand's progress report highlighted increased boat and workplace inspections, but the U.S. has said those do not combat trafficking in an industry where "overall impunity for exploitative labor practices" is seen. The U.S. recommends increased prosecutions of employers involved in human trafficking.

The problem is also rampant in the country's notorious sex industry. More than three-quarters of trafficking investigations launched last year in Thailand involved sexual exploitation. Thai girls and women were abused along with those from neighboring countries.

Another challenge surrounds the recent influx of Rohingya Muslims. An estimated 75,000 have fled Myanmar since communal violence exploded there two years ago, according to Chris Lewa of the nonprofit Arakan Project. The Buddhist-dominated country considers Rohingya to be noncitizens from Bangladesh, though many were born in Myanmar.

Many Rohingya brought to Thailand are held at rubber plantations or forest camps by armed guards until they can find a way to pay the typical asking price of $2,000 for their release, according to victims and rights groups. Those who get the money often cross the border into Malaysia, where tens of thousands of Rohingya have found refuge. Those who don't are sometimes sold for sex, forced labor, or they are simply left to die.

The Thai government, however, does not address these asylum seekers as trafficking victims in its report. It said fleeing Rohingya enter Thailand willingly, even though "most of them fall prey to smugglers and illegal middlemen." However, Vijavat, the Thai ambassador, said some cases are now being treated as trafficking.

Rights groups allege corrupt Thai officials are sometimes involved, including deporting Rohingya straight back into traffickers' hands.

"I believe we have more good officers than bad ones," said police Col. Paisith Sungkahapong, director of the government's Anti-Human Trafficking Center. He said migrants in the country illegally "are pushed back through proper channels. Immigration will contact their counterpart in Myanmar or whichever country, and make sure they return there safely."

In a letter last month to U.S. Secretary of State John Kerry, a group of 18 human rights groups and labor organizations highlighted the Rohingya issue, while urging the U.S. government to put more pressure on Bangkok to crack down on the seafood industry and keep fish caught by slaves from ending up on American dinner tables.

"The (Thai) government continues to be at best complacent, at worst complicit, in the trafficking of migrant workers from neighboring countries to provide inexpensive labor for export industries," they wrote.

___

After a year on the boat, Chan finally started getting paid: about $87 every two months. He continued working for a total of three and a half years, until he started coughing blood and became too weak to continue.

When he asked the captain if he could go home, he was told to get back to work.

"I thought it was better to die by jumping into the water than to die by being tortured by these people," he said. "When I was about to jump, my friend grabbed me from the back and saved me."

His crew members instead convinced him to slip away the next time they made land, and he eventually escaped into Ambon where a local woman helped him get treatment for tuberculosis. After recovering, he decided to stay with her, and she treated him like a son. He worked odd jobs for the next four years, but never stopped dreaming of home.

Finally, at age 24, he found someone at Indonesia's immigration office willing to help. And in March, the International Organization for Migration arranged for him and 21 other trafficked Burmese fishermen to fly home.

Hours before boarding the plane, Chan wondered what would be left of his old life when he landed. More than seven years had passed without a letter or a phone call. He had no idea if he would be able to find his family, or even if they were still alive.

"After I knew the broker sold me into slavery ... I felt so sad," he said. "When I left Myanmar, I had a great life."

___

Associated Press writers Robin McDowell in Yangon, Myanmar and Matthew Pennington in Washington contributed to this report.

Muslims in Rakhine (Arakan) state, and particularly those of the Rohingya minority group, continue to experience the most severe forms of legal, economic, religious, educational, and social restrictions and discrimination. The government denies citizenship to Rohingyas. Without citizenship, Rohingyas lack access to secondary education in state-run schools, cannot be issued government identification cards (essential to receiving government benefits), and face restrictions on freedoms of religion, association, and movement. In some areas, Muslims were allowed to gather for worship and religious training only during major Muslim holidays. The government recently ordered the destruction of mosques, religious centers, and schools. In his 2013 report, the UN Special Rapporteur on Human Rights in Burma again reported to the UN Human Rights Council on the systematic and endemic discrimination against the Muslim community. 

In the past year, Rohingya asylum seekers have been turned away from Bangladesh and Thailand, including being forcibly pushed back to sea by Thai military forces. Untold numbers have died attempting to seek refuge in third countries. About 300,000 Muslim Rohingya live, often in squalid conditions, in refugee camps in Bangladesh, Thailand, and other Southeast Asian countries, and face discrimination, trafficking, and other hardships.

As three-month-old Asoma Khatu approached her final, labored breaths, her neighbor Elia, a 50-year-old former farmer, dug through the strongbox holding some of the last medicines in this camp for Myanmar's displaced Rohingya. 

First, some paracetamol for the severely malnourished girl's fever and a wet towel for her forehead. Then some rehydration salts for her diarrhea. There was nothing else left.

The death of Asoma in a dusty, stifling hot camp a two-hour boat ride from Sittwe, capital of Rakhine State in west Myanmar, is part of a growing health crisis for stateless Muslim Rohingya that has been exacerbated by restrictions on international aid.

"I think my child would have made it if someone was here to help," Asoma's mother, Gorima, told Reuters, as she cradled the girl's shrouded, almost weightless body in her arms.

In February, Myanmar's government expelled the main aid group providing health to more than half a million Rohingya in Rakhine State - Medecins Sans Frontieres-Holland (MSF-H) - after the group said it had treated people believed to have been victims of violence in southern Maungdaw township, near the Bangladesh border, in January.

The United Nations says at least 40 Rohingya were killed there by Buddhist Rakhine villagers. The government denies any killings occurred.

Attacks on March 26 and 27 on NGO and U.N. offices by a Rakhine mob angered by rumors a foreign staffer for another group, Malteser International, had desecrated a Buddhist flag led to the withdrawal of aid groups providing healthcare and other essential help to another 140,000 Rohingya living in camps after being displaced by Buddhist-Muslim violence since 2012.

The government had pledged to allow most NGOs to return to full operation after the end of Buddhist New Year celebrations this month.

But so far only food distribution by the World Food Programme has returned to normal, and Rakhine community leaders in the state government's Emergency Coordination Centre have imposed conditions on others wanting to go back.

NGOs will only be allowed to operate if they show "complete transparency" in disclosing their travel plans and projects and are not seen to favor Rohingya, said Than Tun, a Rakhine elder who is part of the center. Neither MSF-H nor Malteser are being allowed back in, he said.

"CONCENTRATION CAMP"

With foreign aid largely absent, every day of delay is measured in preventable deaths.

No one is there to count them accurately, but the average of 10 daily emergency medical referrals before aid groups left are no longer happening, said Liviu Vedrasco, a coordinator with the World Health Organisation.

Extrapolating from that how many people could be saved is impossible, Vedrasco said. "It was not ideal before March 27. NGOs were not providing five-star medical care. But they were filling a gap."

Government medical teams have been making limited visits to Rohingya areas, but foreign aid groups say they are inadequate. Most of the slack has fallen to under-qualified Rohingya using whatever is at their disposal.

In Kyein Ni Pyin, nearly 4,600 Rohingya live under police guard and their movements are restricted. They are classified by the government as illegal Bengali immigrants. One foreign aid worker described the area to Reuters as "a concentration camp".

Elia is one of eight people given seven days' training to assist in an MSF-H clinic, which now sits empty. The only medicines he has are those he used on little Asoma and some iodine. Government doctors have made three visits of about two to three hours each, he said.

Eight people, including six infants, have died since the aid group left, he said. The night before a recent Reuters visit, one woman lost her baby during delivery.

"THEY REFUSE TREATMENT"

Win Myaing, a spokesman for the Rakhine State government, dismissed the notion that there is a health crisis in the camps.

"There is a group of people in one of these camps that shows the same sick children to anyone who visits. Even when the government arranges for treatment they refuse it," he said.

The United States, Britain and other countries have called on the government to allow aid groups to return to Rakhine State, to little effect so far [ID:nL6N0MZ4K1].

Appeals by the international community for Myanmar to do more to end persecution of the Rohingya have similarly made little impression on a government that sees them as illegal immigrants and denies them citizenship.

U.S. President Barack Obama, speaking during a visit to Malaysia, said on Sunday that Myanmar would not succeed if its minority Muslim population was oppressed.

He may visit Myanmar towards the end of this year, when it is due to host a regional summit, and he could come under pressure from lobby groups to restore sanctions that have been softened since the end of military rule in 2011.

Opposition leader Aung San Suu Kyi, who led the fight for democracy while the military ran the country and now sits in parliament, has faced rare criticism abroad for her failure to defend the Rohingya.

GETTING WORSE

Visits by Reuters to the remote Kyein Ni Pyin camp, as well as several camps near Sittwe, reveal a widespread struggle with illness. In low-slung huts, dozens of mothers showed their emaciated children. There is no data to compare malnutrition rates to when NGOs were forced to leave.

Along the bustling main street of the Thae Chaung camp outside Sittwe town, thatched bamboo stalls that sell a limited selection of drugs have become makeshift clinics.

Mohammad Elyas, a 30-year-old who sold medicine in Sittwe's market before he was driven out by marauding mobs in 2012, displays his laminated qualifications near the front, including a degree in geology and a certificate in traditional medicine.

Medicine is sporadically supplied by sympathetic Rakhine Buddhists in Sittwe, but they run the risk of retribution from their own community for doing so.

At least 20 to 30 people come each day seeking treatment, Elyas said. "Week by week it's getting worse."

"I'm just trying to save as many lives as possible. Even though I don't have the proper qualifications, if I don't do this work, people will die," he said.

(Additional Reporting by Min Zayar Oo and Aye Win Myint; Editing by Mike Collett-White)