SAN FRANCISCO (CBS SF) — The victim in a fatal shooting in San Francisco’s South of Market neighborhood on Wednesday was identified by the city medical examiner’s office as 21-year-old Frank Beltran.

Police have not released many details about the shooting, which was reported at 3:22 p.m. in the area of Fourth and Mission streets in front of the City College of San Francisco downtown campus at 88 4th St.

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A witness said the gunman approached the victim from the other side of the street.

“He walked across the street from right here and he had the gun in his hand the whole time, and he aimed it right at the guy, pulled the trigger about four times, and he looked around frantically and then sprinted as fast as he could,” said witness Ethan Brasseur. “It was probably one of the scariest moments of my life.”

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Beltran was taken to a hospital and was pronounced dead.

Mission St. was blocked off between 2nd and 5th Streets as police searched the Yerba Buena Gardens parking garage, where the suspect was arrested.

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He was identified as 23-year-old Jose Alvarez. He was booked on murder and weapons charges. The investigation remained active and anyone with information was asked to call the SFPD 24 Hour Tip Line at 1-415-575-4444 or Text a Tip to TIP411 and begin the text message with SFPD.