Saydul Islam, 17, saw a Rohingya mother and her two children killed over food by several Bangladeshi men on their overcrowded boat.
His story is just one of dozens shared by more than 670 Rohingya and Bangladeshi survivors who were rescued off Indonesia's Aceh province and brought to shore last Friday.
Saydul told The Sunday Times the Rohingya were travelling from Myanmar in one vessel, but when the boat reached the waters off Thailand, the Bangladeshis got on board as well.
Tension developed between the two groups in the cramped boat, which led to quarrels and fights over food and water. This was when the strong turned against the weak, said Saydul, who could speak a little English.
The Rohingya group comprised mostly women and young people, many of them children, while the Bangladeshis were all men, he explained.
"The Bangladeshis wanted one woman's food but she refused.
"She said no because she had very little food and she also had children to feed. (So) they killed her," Saydul said, adding that the men slit the woman's throat before throwing her body and her young children overboard.
Sobika Begom, a 17-year-old Rohingya, said a group of Bangladeshi men attacked and killed her uncle, his wife and three of their children after an argument.
"The parents and the oldest son were slain and thrown into the sea and the rest were just thrown overboard," she told The Sunday Times through an interpreter as her cousin, her only surviving family member, stood next to her. Sobika said the men who killed her uncle's family were at the camp too.
While the Rohingya Muslims are willing to risk their lives to avoid persecution in Myanmar, the Bangladeshis are mostly looking for work to support their families back home.
However, many said they fell prey to so-called "agents" by offers of well-paying jobs in Malaysia.
Bangladeshi Abdul Ghoni, 20, said that when their boat reached the waters off Thailand, the human traffickers contacted his parents in Bangladesh and demanded money.
The same thing happened to others, he said.
"The deal was that the agent would take us by land from Thailand across to Malaysia. But after my parents made the payment, we never landed in Thailand," Mr Abdul said.
"Later, the ship's captain took off on a speed boat. We were all left on the boat."
Mother-of-two Soku Tara, 24, said she took the dangerous sea journey to join her husband, who is in Malaysia.
When the engine stalled and the boat began to sink, the people grew desperate.
They spotted some Indonesian fishermen and shouted for help. Said Madam Soku: "If it weren't for the fishermen who saved us, we would have been eaten by fish."
After they were rescued and taken to shore, the Rohingya and the Bangladeshis were put in separate places at Kuala Langsa, which had ceased operating as a port more than 10 years ago.
Now the Rohingya refugees stay in a 12m-by-18m tent set up in the rear of Kuala Langsa, while the Bangladeshis were put up in former warehouses.
About 15 people were put on the drip in a tent set up for the sick.
Rohingya refugee Sekarabibi, 14, found the camp uncomfortable because it was hot in the day and full of mosquitoes at night. Some were ready to go home after their ordeal.
But when asked if she wants to return to Myanmar, Sekarabibi said: "No, let's face whatever we have to face here. Back home, they burn houses and attack you."
This article was first published on May 17, 2015.
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