Bangkok - Thailand's military last month pushed out to sea at least 992 Rohingya refugees - stateless Muslims from Myanmar - leaving 400-500 missing and feared dead, a Rohingya-watch group announced Monday.

In what is turning into a major embarrassment for Thailand's new government under Prime Minister Abhisit Vejjajiva, the Arakan Project has provided evidence based on the testimony of survivors that the Thai Navy pushed back to sea some 992 Rohingyas between December 18 to 30 in engineless boats on the high seas.

"There could have been more people pushed back but these are only the cases we know about from the testimony of survivors," said Chris Lewa, coordinator of the Arakan Project, a non-government organization that has monitored the persecution of the Rohingya minority group in Myanmar's Arakan State for years.

News that the Thai military was pushing Rohingya refugees out to sea came to light last month when the Indian Navy on December 18 rescued 107 people on a boat who claimed that they had been put to sea on the engineless craft by the Thai Navy and sent adrift.

According to the survivors, about 300 of the 412 refugees had drowned when they jumped overboard to try to swim to shore.

Another group of 580 Rohingyas was detained in Thailand on December 29 or 30, and shoved back to sea on their five boats after the engines were removed, said Lewa.

Of this group, some 193 onboard were rescued in Indonesia's Sabang Island in Aceh on January 7 and an another boat with 150 onboard was rescued in Tillanchang Island, India, on January 10.

On January 6, another 81 Rohingyas was rescued by Thai fishermen, and have since been put under Thai military custody again, said Lewa.

The Arkan Project was still checking whether this group was part of the 580 pushed back on December 30.

There are still between 400 to 500 of the refugees unaccounted for, she said.

The Thai miliary has denied accusations that they pushed the Rohingyas out to sea, although officials acknowledge that they see the Myanmar-Muslims as a security threat, suspecting them of coming to Thailand to join Thai-Muslim insurgents in southern Thailand's Pattani area.

"Rohingyas have a different status among refugees trying to come to Thailand because Rohingyas are branded as a national security threat, simply because they are Muslims," said Sunai Pasuk, the Thailand representative for the New York-based Human Rights Watch (HRW).

HRW and other human rights groups have been calling on the Thai government to include the UNHCR in their refugee screening process, rather than leaving it up to the military as has been the case for the past four-five years.

Thai authorities have been pushing Rohingyas back to Myanmar for years, but may have turned to using more drastic measures because Myanmar has refused to accept the refugees.

"The Rohingyas are a stateless people. They are not considered to be citizens of Myanmar," said Lewa.

The Rohingyas are a minority group in Myanmar, numbering around 800,000, who have been refused citizenship because they are deemed to be Bangladeshi nationals who have recently migrated to the country.

Lews called on Thailand to join hands with the international community and UNHCR in fining a long-term solution to the Rohingya problem. (dpa)