BANGKOK, May 28 (Xinhua) -- The leader of Thailand's opposition Democrat Party Sunday urged the government to find out the truth behind a discovery of more than 500 graves in the Muslim-majority southern most provinces of Pattani, Yala and Narathiwat.

    Abhisit Vejjajiva, the president of Democrat, cited a report made by Kraisak Choonhavan, former chairman of the Senate Foreign Affairs Committee, who said the Central Institute of Forensic Science had tabulated more than 500 unidentified corpses in the two troubled provinces.

    The Foreign Affairs Committee had followed the issue and it was believed that the physical evidence indicated deaths occurring about late 2004, Abhisit said.

    The Democrat leader said that the government should clarify the matter to the public because ongoing violence in the restive South resulted in partly from a lack of trust among the people.

    Meanwhile, the Central Institute of Forensic Science said on Sunday that the unmarked graves appear to hold bodies of slain migrant workers from neighboring Cambodia and Myanmar.

    Most of the bodies were found in late March in Pattani, one of three insurgency-hit provinces in southern Thailand. They were buried in unmarked graves at cemeteries for the region's ethnic Chinese community, the Central Institute of Forensic Science said.

    About another 30 bodies were found in Narathiwat province, and a few others in Yala Officials said most of them were killed. Enditem