A city worker headbutted a bearded man on a packed commuter train to London after claims he was 'trying to fight other passengers'.
Commuters cheered as the smartly dressed worker dealt with the man after social media reports claimed he was shouting abuse and being agressive.
Video footage then shows a sharp-suited man arguing with the passenger and restraining him by holding his wrists.
The bearded passenger then starts shouting "look at me I'm stupid! Look at me!", before the suited man head-butts him - sending him backwards into a door.
The attack was met with a mixture of gasps and cheers from passengers on the crowded train.
It is unknown who filmed the video, which was taken on a train from London to Southend-on Sea, however it has been circulating on social media since yesterday evening.
Several people praised the suited man online - with one saying: "Give the man a meal, an award, he is a deserving recipient of a knighthood."
Another wrote of the head-butt: "Good technique too, holds his wrists prior to interception, locked and loaded... deploy warhead."
The bearded man was allegedly taken off of the train at Upminster station where he was arrested by police.
In another video capturing the aftermath, the suited man is shown restraining the bearded passenger on the platform floor with his hands behind his back - with the help of two passersby.
The person recording can then be heard saying "this guy's crazy" as fellow commuters laugh in the background.
London Transport Police have been reached for comment.
