Bangkok  - Thai police have arrested a US national on charges of robbing a bank after finding 147,000 baht (4,323 dollars) stashed in his underwear, police said Thursday.

Harold Guyear, 54, of New York confessed to the crime after police detained and searched him Wednesday in a field near the robbed bank, police Lieutenant Colonel Sakorn Jermkhuntot said.

"He said he committed the robbery because he had no money," Sakorn said.

Guyear - wearing a khaki suit, hat and scarf over his face - is accused of entering a Siam City Bank branch Wednesday in Phathum Thani, a province neighbouring Bangkok, jumping over a counter, taking 147,000 baht in banknotes out of a teller's drawer and dashing out of the bank into an adjacent department store without being stopped by security guards.

"He didn't have a gun, but he was very quick," Sakorn said.

Although Guyier initially claimed to be innocent, he confessed to the crime after police discovered bundles of Thai banknotes in his underwear.

"The American has been living in Thailand on and off for several years, leaving every few months to renew his tourist visa," Sakorn said. (dpa)