CCTV footage shows a British couple and their son beaten unconscious in Thailand by a local gang IBTimes UK

Four Thai men who beat a British family unconscious have been jailed for two years each. Rosemary and Lewis Owen were visiting the tourist resort of Hua Hin with their son, also named Lewis, who accidentally bumped into one of the defendants – only to be knocked out cold by the gang of drunk men.

The incident took place during Thai New Year celebrations in April. Attackers Uphattha Baithong and Yingyai Saengkhamin, both aged 32, and Siva Noksri and Chaiya Jaiboon, both aged 20, received a four year sentence each, but this was reduced to two years after they confessed to the assault.

Following the brutal attack, Rosemary Owen, then 65, was left with brain injuries which required surgery after doctors found swelling. Lewis Owen Sr, 68, and Lewis Owen Jr, 43, required six and 16 stitches respectively after the assault, which was captured on CCTV.

Footage showed a crowd of onlookers as the perpetrators carried out the violent onslaught, which continued even as the family were knocked to the floor by a barrage of kicked and punches. One man who tried to intervene was also punched.

The defendants admitted they were drunk and apologised for their behaviour, according to the Bangkok Post. Jaiboon claimed he thought one of the British tourists had hit a friend of his.

Following the court ruling, the men were transported directly to Prachuap Khiri Khan Provincial Prison.

The incident only went viral after footage was released to the public, which sparked international anger. The video shows bystanders looking on as the beating unfolded, stepping in only once it was over. While the clip was released the the public, officers reportedly refused to show it to the Owens as it was "too violent".

Rosemary Owen and her husband had been frequent visitors to Thailand since the the 1980s, but vowed never to return after the assault.