DSI spokesman Colonel Piyawat Kingket said yesterday that there was strong evidence against all 16 suspects in the case, including Vatana. The DSI's request runs counter to a decision by a director of special investigation at the Office of the Attorney General to spare Vatana on the grounds that there was no concrete evidence against the politician. "But we even have witnesses who saw Vatana on the encroached land," Piyawat said.

According to the DSI, Vatana, through Inter Palm Oil Industry Co Ltd, hired people to encroach on protected forest land in Phang Nga's Kapong district, made use of the resources there and falsely obtained documents granting rights to the land.

The encroachment covered 13,000 rai of land, which was then mortgaged to a bank at a value of more than Bt10 billion.

Piyawat said the mortgage had been arranged through an official assistant to Vatana while he was deputy interior minister. Vatana is currently being sued by the bank to repay a Bt15-billion debt arising from the mortgage.