British family brutally attacked while on vacation in Thailand (VIDEO)
The footage, captured by security cameras and later posted on social media, shows a group of men punching and stomping on the family's faces, and kicking their bodies.
The attack on the victims - a 65-year-old woman, a 68-year-old man, and their 43-year-old son - began after "the son accidentally bumped into one of the Thai men," Police Col. Chaiyakorn Sriladecho said, as quoted by AP.
The perpetrators only stop when the victims are seen lying apparently unconscious on the ground. Bystanders rush to their aid after the men leave.
The assault took place in the beach town of Hua Hin on April 13, as the family was walking down a crowded street amid Thai New Year festivities.
Thai authorities say they have arrested four suspects who are in their 20s and 30s. Three of the men were arrested within days of the incident, while the fourth was detained on Thursday, Chaiyakorn said.
"The men say they are sorry and that they wouldn't have done this if they weren't drunk," he added.
The mother received serious eye and head injuries which caused a build-up of fluid in the brain and required an operation. The father and son suffered head injuries which required stitches.
It comes just one month after four French tourists were assaulted on the island of Koh Kut. The group included a mother and daughter, both of whom were raped.
Two British backpackers were murdered on the island of Koh Tao in 2014, with autopsies showing the couple had been severely beaten and the woman raped. Two Myanmar migrants were convicted of the crime based on DNA, though rights groups say the evidence was questionable.