A 23-year-old Minneapolis man was charged Friday with assaulting a 75-year-old Metro Transit bus rider, who authorities say had told the suspect and his friends to keep their voices down on the bus.

According to the Hennepin County attorney’s office, Leroy Davis-Miles was charged with first-degree assault in the Wednesday attack.

The victim was in critical condition Friday and may not survive the brain injury he suffered in the attack, County Attorney Mike Freeman’s office said.

Prosecutors say the victim and Davis-Miles and his companions all boarded a bus Wednesday afternoon. At one point, bus surveillance video showed the victim asking the noisy group to quiet down.

The young men grew hostile and threatened to beat the man when he got off the bus.

When the older man got off the bus at the Chicago-Lake Transit Center, Davis-Miles and his companions also exited. According to surveillance video and witnesses, Davis-Miles walked next to the man for a short distance before punching him once.

The victim fell backward and hit his head on the pavement.

Prosecutors say Davis-Miles and one of his friends shook hands in a “congratulatory manner” and then rummaged through the man’s pockets.

Police used facial recognition software to help identify Davis-Miles.

He was arrested at his home Thursday, and clothing matching that seen in the video was seized.

Davis-Miles is expected to make his first court appearance Tuesday.