For more than 20 days they drifted at sea in a rickety open boat exposed to the tropical monsoon. Their meagre supplies of food and water soon ran out. The 220 Burmese migrants - all men apart from a boy of 13 - were packed in so tightly they could do little but stand jammed shoulder-to-shoulder. As the craft drifted, 22 of them succumbed to dehydration or exposure and died. The bodies were thrown overboard.
The rest, now starving and many in a critical condition, were discovered in their ramshackle vessel off the coast of northern Sumatra by Indonesian fishermen late on Monday.
If their survival was remarkable, the story of how they came to be there is becoming commonplace. According to the survivors, their plight was caused by Thai security forces who are now facing international scrutiny for their treatment of illegal migrants desperate to find work in their country.
The migrants were from Burma's Rohingya Muslim minority. They had been detained late last year by Thai authorities and taken to a remote island where they were held for two months and, they say, beaten before being put on the boats and left to their fate. Theirs was one of nine craft carrying 1,000 Rohingya that were set adrift from the island with little food and water by the Thai military.
Under intense international pressure the Thai prime minister, Abhisit Vejjajiva, has said the influx of Rohingya migrants was putting jobs at risk, but promised to investigate the scandal. However he has placed the inquiry in the hands of the Internal Security Operations Command, the very unit accused of the abuses. Vejjajiva, who was educated at Eton and Oxford, won office with the army's backing and still needs it support, but, observers say, he wants to live up to his promises of improving human rights.
Meanwhile the litany of tales of Rohingya abuse has been growing. Last month 107 Rohingya migrants were picked up by the Indian coastguard off the Andaman islands. They said that the Thai army had rounded them up and held them on the southern island of Koh Sai Daeng.
According to testimony from the survivors, soldiers shot four and threw them into the water to encourage the other 412 migrants to board an open barge. On 18 December it was towed out to sea and cut free with just four barrels of water and two sacks of rice. After drifting for 15 days 300 tried to swim ashore when they came within sight of the Andaman Islands. They are still missing.
In another incident, a boatload of 193 Rohingya was discovered near Indonesia's Sanbang island, off Aceh, on 7 January after they were apparently set adrift by the Thai army. They were among four boatloads containing 580 migrants pushed back by the Thai authorities sometime in late December.
The migrants picked up on Monday were discovered huddled in their boat which had been lashed together with rope. They had not eaten for a week and were so tightly packed in the tiny vessel there was only room to stand.
"Fishermen found a wooden boat without an engine drifting in the sea with 198 Myanmar [Burmese] migrants," said Indonesian navy officer Tedi Sutardi. "They said the Thai authorities towed them out to sea and set them adrift.
"Their boat was small. It's only 12m [40ft] long and 3m wide. It had almost come apart and was held together with ropes. They were standing in the boat for 21 days because there was no space to sit. It's a miracle they survived."
At least 56 - including the 13-year-old - were being treated at Idirayeuk hospital for severe dehydration, while the rest were being cared for at the town's district office.
Sutardi said the survivors recounted how Thai security forces beat them after they were detained for illegal entry.
"We were caught by the Thai military along with 1,000 other Rohingya people," Rahmat, 43, told AFP news agency from hospital. "We were brought to an island and stayed there for two months before being thrown out to sea on wooden boats without engines.
"During the journey about 20 people among us died because there was no food and water. We performed prayers in the boat for them before we threw the bodies into the sea ... Almost every day someone would die."
The Rohingya told how they left Burma's Rakhine state to escape their brutal treatment at the hands of the military junta. Thousands cross into neighbouring Bangladesh to board fragile boats to make the voyage to Thailand during the six-month dry season when seas are calmer. They hope to make an overland journey to find work in Muslim countries such as Malaysia or Indonesia, guided by people smugglers who charge up to £500 each.
Human rights groups have demanded the Thai government get to the bottom of the tragedies that have befallen the Rohingya.
"This is a double tragedy for the Rohingya who have long suffered abuse in Burma and now when they're driven to the sea in desperation they find no safe haven," said Sam Zarifi, Amnesty International's Asia-Pacific director. "It raises very, very strong grounds for concern about the conduct of the Thai military towing people out to sea knowing their vulnerability. The Thai government must investigate and see it doesn't happen again."
Joel Charny, vice-president of Washington-based Refugees International, said the case only served to amplify the desperate need of the Rohingya for recognition.
"The Rohingya need protection and asylum," he said. "Thailand has said it's unwilling to grant that. But this is a problem that won't go away."
Backstory
The Rohingya are a Muslim minority in predominantly Buddhist Burma. Most of them live in the western state of Rakhine which borders Bangladesh.The Burmese military government does not recognise them as one of the country's approximately 130 ethnic minorities, and with few legal rights the Rohingya are subjected to various forms of extortion, arbitrary taxation, land confiscation, forced labour, torture and extrajudicial execution, according to Amnesty International.
Since Burma won independence in 1948, thousands of Rohingya have fled to Bangladesh where more than 200,000 now live a perilous, stateless existence. Rohingya are restricted from travelling inside Burma, and those in Bangladesh have little prospect of returning home. As a result, many have been desperate enough to put to sea during the dry season in small boats sailing from Bangladesh or Burma, often turning up in Thailand, Malaysia or as far away as Indonesia
Their plight has taken on an extra urgency in the last few months with claims that the Thai authorities detained hundreds of Rohingya as illegal workers, beat them and then abandoned them on motorless boats.
The drifting boat reported yesterday was the second load of Rohingya to arrive in Indonesia in a month. Other boatloads have been found near India's Andaman Islands. The Thai government deny abandoning the Rohingya and say people traffickers are behind the recent influx into the country.
Thailand is a staging post before they are transferred to a third country, the head of a Thai government committee, Jehraming Tohtayong, said this week.