"They could be Thai nationals. It is only that they had Malaysian currency with them when they were arrested. Maybe they wanted to enter Malaysia," Abdullah was quoted as saying by the New Straits Times.

"However, without any other solid evidence, I deny that those people were Malaysians or that they were trained in Malaysia," he was quoted as saying from Saudi Arabia during a trip there.

Violence in southern Thailand is a sensitive bilateral issue and Thai officials have in the past accused Malaysia of failing to prevent insurgents from crossing the porous border to stage attacks.

Malaysia has denied those charges, as well as accusations of insurgency training camps within the country.

Thailand also believes that militants behind the insurgency are abusing dual citizenship to escape across the border with Malaysia after committing attacks.

In the raid on a mosque in Narathiwat, Thai soldiers captured the militants and seized about 2,500 dollars worth of Thai baht and Malaysian ringgit, as well as weapons, radio communication equipment and medical supplies.

Abdullah said Malaysia was not ignoring information passed on from Thailand about suspected militants, but pointed to difficulties in tracking them down.

"It is not a question of having easy access as many of these people follow the procedures and enter the country using legal travel documents," he was quoted as saying in the Star daily.

Abdullah said the countries were exchanging lists of people with suspected dual citizenship.

"By exchanging the name lists of both sides we will be able to determine how many people actually hold dual citizenship," he said.

The two countries last month agreed to boost cooperation to end three years of separatist unrest in the Thailand's south in which 2,000 people have died.

Agence France-Presse