A man walked into a Starbucks downtown and told workers he had been stabbed.
Emergency personnel were called to the Starbucks on Market Street and Fourth Avenue just after 6 a.m.
San Diego Fire-Rescue crews responded to help the injured man while San Diego police detained a possible suspect.
The victim was taken to a nearby hospital. No details were given on the extent of his injuries.
The Starbucks is located on the same corner as Hooters and the Royal India restaurant.