Thailand has blamed the flight of 131 Thai Muslims to neighbouring Malaysia on an Islamic separatist group, saying it wanted to internationalize the conflict along the border.

The government rarely singles out any group in the 20-month conflict, usually referring only to unnamed militants in the Muslim-majority southern provinces.

But in a statement released late Wednesday, foreign ministry spokesman Sihasak Phuangketkeow said the Patani United Liberation Organisation (Pulo), sparked the incident and alerted the UN refugee agency in a bid to internationalize the unrest.

Sihasak accused Pulo of stirring rumours to frighten the villagers into fleeing to Malaysia.

At the same time, he said Pulo had created a new human rights section called the Patani Malay Human Rights Organisation (PMHRO) to take up the cause of the villagers and tarnish Thailand's image through its website.

"As soon as the incident occurred, this PMHRO contacted the (UN High Commissioner for Refugees) office in Switzerland ... and said that those Thai villagers had fled for fear the Thai government would kill them after imposing the emergency decree," Sihasak.

UNHCR interview

The emergency decree came into force in the three southernmost provinces in July and allows authorities to detain suspects for up to 30 days without charge. It also gives authorities immunity from prosecution.

The villagers who fled had taken part in the Tak Bai protest last October, one of the bloodiest days in the conflict, when 87 demonstrators died as authorities broke up a demonstration, Sihasak added.

Most died of suffocation when they were detained, bound and then piled onto military trucks.

The UNHCR on Tuesday started interviewing the 131 Thai Muslims sheltering in Malaysia after they fled last week, despite opposition from Bangkok.

Malaysia has given temporary shelter to the Thais pending investigation of their status and reasons for leaving, but has voiced concern over the prospect of more Thais fleeing across the border.

Nearly 900 people have been killed in the past 20 months in Thailand's southernmost provinces, in attacks which analysts and authorities blame on Islamic separatists, organised criminals and drug dealers.