An elderly British couple and their son were savagely attacked during a family vacation in Thailand in the latest blow to the country's image as a welcoming tourist paradise. Police said Thursday they have arrested three alleged attackers and are looking for one more.

A video of the attack was captured by overhead security cameras and posted this week on social media. It has stirred shock and outrage over its brutality and the ages of the elder victims, a 65-year-old woman and 68-year-old man from Scotland.

The attack marks the latest act of violence against tourists in the Southeast Asian country.

Police Col. Chaiyakorn Sriladecho said the attack started after "the son accidentally bumped into one of the Thai men." All four suspects are Thai.