The incident was first reported around 5:00 p.m. in front of a store in the 100 block of Geary.
Police say the shooting was the result of an altercation between two men, but it is unclear why they were fighting.
The 21-year-old was rushed to the hospital in critical condition where he later died, SFPD said.
One suspect is in custody.
No further details were released.
Police Activity at Union Square, traffic will be impacted. #SFPD . Wide area is closed, traffic diverted.— R. Vaswani (@sfvas) October 2, 2020
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