Photos:Elderly British couple and their son beaten unconscious by thugs in Thailand

A witness who saw a British couple and their son beaten unconscious has described how he tried to help them but was attacked so violently he now needs surgery.

CCTV footage captured the attack at around 2am in the popular tourist resort of Hua Hin, where the elderly couple and their middle-aged son were celebrating Thai New Year.

The row appears to escalate from nowhere as the woman is punched to the ground while the men are being overwhelmed by punches and kicks in the background.

A witness, calling himself 'Usual Suspect' on the Hua Hin internet forum, said a group of Thai youths had been looking for trouble in the area during the Songkran New Year water splashing holiday.

He claims he was walking with his wife and tried to intervene, pushing a youth away who was beating the woman, but was himself attacked and he now needs dental surgery due to his injuries. 

'The girls in the bar I was in all night waved goodbye to two elderly customers and their son and my wife and I followed only seconds after them.'Within 20-30 metres of leaving the bar the Thais were punching the 65-year-old lady in the face!! 'The elderly gentleman was down on the floor and their son was beaten very badly!'At this point I caught up to the scene and pushed one of the youths away from the woman. I got severely punched and kicked for my troubles, but felt the need to protect this frail lady.

'Not one person (other than myself) came to aid these old folk and they ended up laid in the road bleeding..so if you're still out in the wee hours tonight please be alert.

'These pockets of youths were intent on causing harm, and did blend in with all others beforehand.

'The three of them are still hospitalised, and I will need cosmetic dental work done.

It is not clear in the clip what is being said to provoke the outbreak of violence.But a melee ensues between the tourists and the gang members, with the British woman, who is believed to be in her 60s, approaching one of the gang and speaking to him.

The man then punches her in the face and knocks her to the ground, while both men are being kicked and punched in the uproar. As she tries to sit back up, one of the gang kicks her violently in the jaw and knocks her out. 

The three holidaymakers were left knocked out cold and lying in the street as their attackers disappear into the crowds of passersby during the Songkran festivities. 

Police are using the CCTV footage from a camera at the entrance to a small street of bars to trace the attackers.

They say they have arrested four suspects and are confident of arresting others.