Police are searching for three young men after a light rail passenger in St. Louis was attacked after being asked what he thought about the "Mike Brown situation."

Officers released details Friday after a passenger who wasn't involved posted video of the attack on social media.

The 43-year-old victim told authorities that one of the men asked to use his cellphone. When he refused, the man asked what he thought about the Brown "situation," then punched and kicked him.

The two other men struck the victim. All three young men got off the MetroLink train Monday.

The victim declined medical treatment.

Brown, an unarmed, black 18-year-old, was fatally shot by a white Ferguson police officer in August.

The victim in the train incident is white. His attackers are black.