When the Myanmar navy seized a boat used by people smugglers last week, it announced that the 200 people found aboard were mostly Bangladeshis seeking better economic prospects in Southeast Asia.

The message was clear -- that very few of the people on the boat, and by extension in the wave of Asian "boatpeople" drifting on the Bay of Bengal and the Andaman Sea, were members of Myanmar's Rohingya minority. Myanmar denies discriminating against the Rohingya or that they are fleeing persecution.

But in interviews with Reuters, people who were on the boat said between 150-200 Rohingya were aboard at one point. Many were quietly whisked away by the traffickers in the week before the navy brought the ship to shore, they said. The number is far larger than what Reuters reported previously.

"All of the Rohingya got off the ship. The Bangladeshis stayed behind," said a 27-year-old Rohingya woman who was on the boat with her five children. All six of them returned to their village of Thek Kay Pyin before the ship was seized last Thursday.

It was not possible to independently confirm the account of the woman, who identified herself as Arafa. Like many Rohingya, she uses only one name. But six other villagers said they were among the scores of Rohingya taken off from the boat.

It was not clear why the traffickers would only take the Rohingya off the boat. Matthew Smith, the executive director of the Southeast Asia-based Fortify Rights group, has said in testimony to the U.S. Congress that Myanmar's security forces are complicit in and profit from the trafficking. The government has dismissed the accusation.

Meanwhile, protesters hold up a banner in Yangon yesterday ahead of a demonstration against Rohingya boat migrants originating from Myanmar, who are largely seen there as illegal immigrants from Bangladesh and referred to as “Bengali”. Photo: AFP

 Last week, Reuters reported that at least eight people found on the boat were Rohingya. The government, which had initially said all on board were Bangladeshis, said eight were "Bengalis" from Myanmar, the term it uses for the Rohingya.

Zaw Htay, an official in the president's office, said on Tuesday he was not aware that any other people were on the boat, other than the Bangladeshis and the eight "Bengalis".

"Our office did not get any information that some of them left before," he told Reuters.

The Myanmar government invited United Nations officials to meet the Bangladeshi migrants and the event was given wide publicity on state television.

After a crackdown on people smugglers in Thailand blocked trafficking routes earlier this month and forced them to abandon some ships, thousands of migrants have washed ashore in Malaysia and Indonesia. Others are stranded on trafficking boats off the shores of several Southeast Asian countries.

The migrant boats contain a mix of people from Bangladesh seeking to escape poverty at home as well as Rohingya, Indonesian and Malay authorities have said.

US Deputy Secretary of State Antony Blinken said last week during a visit to Myanmar that the majority of the more than 3,000 migrants who have landed on Malaysian and Indonesian shores this month were Rohingya Muslims fleeing from "the desperate conditions they face" in Myanmar's Rakhine state.

Rakhine Chief Minister Maung Maung Ohn later told Reuters: "I am disappointed by, and completely disagree and reject such unfounded allegations by the United States."

"This [migration] is human trafficking, not [due to] political or religious discrimination at all."

Other Myanmar officials have said the Bangladeshis claim to be Rohingya to receive UN aid.

Most of Myanmar's 1.1 million Rohingya Muslims are stateless and live in apartheid-like conditions in Rakhine state. Almost 140,000 were displaced in deadly clashes with majority Buddhists in Rakhine in 2012. They are denied citizenship and have long complained of state-sanctioned discrimination.

About 100,000 have fled overseas since 2012, according to the Arakan Project, a Rohingya advocacy   group.

The boat seized by the Myanmar navy was at anchor for about two months off the coast of Myanmar to load up before it was supposed to set sail for Malaysia, the seven villagers and two community leaders, who did not want to be named, told Reuters.

At the time it was filled with about 200 Bangladeshis and around 150-200 Rohingya, Thailand launched its crackdown on traffickers.

Small fishing boats started coming up to the ship and began offloading the Rohingya for about a week before it was brought ashore by the navy last Thursday, the seven Rohingya migrants who came back from the ship told Reuters.

The jobless woman who gave her name as Arafa said she was trying to join her husband in Malaysia and was allowed off the ship for free. Most others had to pay traffickers between $200 and $300 to return to the same villages they tried to escape weeks earlier.

One of them was Mohamed Anyis, 18, from a village close to Sittwe, the capital of Rakhine state. He befriended some of the Bangladeshi men during his two-month stay on the ship.

"We shared scarce food rations and helped the weakest men together," said Anyis.

The migrants were beaten with metal rods and given only two cups of water and a handful of rice a day, Anyis and Arafa said. Anyis still had numerous white scars on his hands and ankles which he said came from repeated beatings.

"As we waited, six Bangladeshi men died of exhaustion. The crew threw their bodies into the sea," he said.

Anyis, Arafa and other villagers separately recognised and correctly named several of the Bangladeshis in photographs Reuters took at the ceremony where the Bangladeshi men were presented to the UN officials, confirming they spent weeks on the same boat.