Tun Tex Hai, aka "Valentino", 56, and his wife Suwaphat Kheeree-phon, 41, were arrested late on Thursday night by Department of Special Investigation (DSI) agents at their home in Phuket's Muang district. Both suspects denied the charge.

Police are waiting for three other people - including a land official based on Koh Yao Island who allegedly assisted both suspects to illegally acquire more than 1,000 rai of land on the island - to turn themselves in to DSI agents next week.

Justice Ministry permanent secretary Jaral Phakdeethanakul said he was confident the DSI had concrete evidence against both suspects.

The DSI took over the case from local police late last year after Koh Yao police found that the land-grabbing scheme involved influential people and land officials.

According to the DSI investigation report, both suspects paid corrupt land officials in 1994 to have title deeds illegally issued on a 300-rai plot of public land and part of a forest reserve. They then obtained a number of loans totalling more than Bt400 million, using the deeds as collateral. The mortgage was granted by two now-defunct financial institutions in which Tun served as a director.

The study of aerial photos and the analysis by land officials participating in the investigation found that more title deeds have been issued on other public and restricted areas covering another 700 rai after 1994.

Hai was appointed honourary consul to Morocco two years ago, representing that country in Phuket, Phang Nga and Krabi. He set up his consul office in Phuket two years ago. Suwaphat was appointed by the Djibouti government as honourary consul early this year.