AYUTTHAYA - Police on Monday arrested a man of Vietnamese descent who allegedly murdered his Thai girlfriend for 'borrowing his money' and then hurled her from a bridge into a river.

wo witnesses told the police that they saw a speeding pickup truck suddenly stop on a bridge in Phra Nakhon Si Ayutthaya district. The driver then hurriedly took a body from the back of the vehicle and threw it into the Chao Phraya river before fleeing.

Police tracked down and found the suspect and his vehicle in Ayutthaya's Bang Pa-in district. Two knives, a cleaver, a spear and a shovel were discovered in the back of the blood-stained pickup truck, police said.

The suspect, Bhumin Somchaidee, 31, is a Thai citizen of Vietnamese descent.

Mr Bhumin allegedly confessed that he murdered Napaphan Siharat, 29, and then threw her from the bridge.

Police said he admitted the victim was his long-time girlfriend. She had been married three times and had children. She had anaemia and asthma and liked to "borrow" his money.

The accused said he plotted to kill her on Sunday, May 27, because she recently borrowed another 4,000 baht from him.

He told police that he stabbed her in the neck twice and then slit her throat and that he planned to bury the body but decided instead to hurl it into the river while driving along the bridge.

Police, however, suspected that Mr Bhumin murdered his girlfriend because he was jealous that she was having an affair with another man.

He was charged with first-degree murder and concealment of a body. Police were still searching for the body of Napaphan in the river.