A man who attempted to break up a fight yesterday afternoon at a Mid-Market BART station is now fighting for his life after one of the participants struck him with a handlebar.

The incident took place just before 3 p.m. at Hallidie Plaza when a 57-year-old man intervened in a physical altercation between two men, 22 and 21.

As the victim tried to quell the argument, the 22-year-old man struck him with a handlebar. Police arrested the suspect at the scene, and the victim was transported to a hospital with life-threatening injuries.

Anyone who has information about this incident is encouraged to contact SFPD via the department's anonymous tip line at 415-575-4444, or text TIP411 with "SFPD" at the start of the message.

Here’s why we usually don’t include suspect descriptions in crime reports.