Officers responded to a report of a man with a gun at about 4:30 p.m. and found him, among several other people, inside a barber shop at the corner of Geneva Avenue and London Street, according to statements by SFPD officials. Then the shooting started.

One man was in critical condition Thursday evening, and one was in serious condition, according to San Francisco General Hospital spokesman Brent Andrew. The officer and two other men were in fair condition.

Andrew did not give any information about the juvenile's condition.

A Police Department spokesman said the initial suspect sustained life-threatening injuries.

Torren Beitler, 22, said he lives nearby and was in a pharmacy next door to the barber shop when he heard "a bunch of gunshots."

He said he later saw an officer and two others taken away by ambulance. A video originally posted on Instagram appeared to show the scene outside the barber shop immediately after the shooting.