The Pakistani embassy in Bangkok has accused the Thai police of trying to obtain confessions under duress from four Pakistani men detained on suspicion of preparing a bomb attack.

An embassy statement accused police of beating up one of the four.

It said there had been a similar incident in June of false terrorist charges being drummed up against Pakistani citizens.

The Thai police have admitted that the Pakistanis in the latest incident were businessmen.

The arrests came as Thailand is engaged in a major security operation ahead of the Asian Games on Sunday.