This is the shocking moment a jealous cannabis seller hit a Canadian tourist in the head with a skateboard - for looking at his girlfriend.

The vendor Pawit Honghaluchai, 33, had been with his friends in the nightlife area of Khaosan Road in Bangkok, Thailand when he attacked the Canadian man, claiming he had been leering at his partner on October 7.

Footage shows Pawit smashing the skateboard into the tourist's head from behind, alarming passers-by. He then continued his assault by kneeing the man's face several times, with his friend also joining in the fray.

The pair were later seen escaping on their motorcycle, leaving their dazed victim bloodied on the pavement.

Police arrived at the scene but could not obtain information from the foreigner as he was unable to give details due to shock.

Police Lieutenant General Thiti Sawang, commander-in-chief of the Thai Royal Police, said: 'We've launched an investigation to find out the suspects' escape route from CCTV cameras in the area.'

Officers tracked down one of the thugs, Pawit, who was identified as a member of a skateboarding gang hanging around the Khaosan Road, a popular destination for backpackers and tourists.

He was said to be working as a vendor along the bustling nightlife strip, selling cannabis drinks to backpackers and tourists.

He was arrested at his home in Nonthaburi province.

Pawit said: 'I saw my friend fighting the Canadian so I went to assist him.

'I used my friend's skateboard to hit the guy, then I hit him two more times in the face with my knee because he was trying to approach my girlfriend.'

Pawit has been remanded in police custody after admitting conspiring to harm another person and causing physical or mental harm.