A man wanted for the murder of his wife, who was set on fire and then stabbed to death in Samut Prakan on Monday, was arrested on Tuesday.

Police identified him as Pisutsiri Chansoda, 42, from Khon Kaen's Ban Fang district. He was arrested in Chachoengsao province.

A search of the vehicle found the knife believed used to kill the woman.

Mr Pisutsiri allegedly confessed to fatally stabbing his wife Nathanan Joomfong, 45, in a jealous rage after seeing her chat online with another man.

Afterwards, he drove to the Bang Pakong river, where he parked near a bridge before police arrested him. He allegedly told police he was about to jump into the river to drown himself.

His wife was savagely murdered about 3pm on Monday in the Bang Pu Industrial Estate.

Witnesses told police they were cleaning their songtaew vehicles when a pickup arrived. A woman weaing only a towel ran towards them, asking for help. The towel was soaked with petrol, they said.

The pickup driver, who was wearing only a pair of trousers, approached her with a plastic container of petrol, which he poured on her and then set her on fire with a lighter. One of the witnesses was burned on his arms and back trying to protect the woman.

The attacker then stabbed the woman with a knife. She ran into a ditch and died. Her killer drove away in the pickup he arrived in.