A 29-year-old man was shot during a gathering inside a downtown apartment complex blocks from Petco Park Monday morning, the San Diego Police Department said.

Several people called SDPD to report hearing one to three shots ring out at the Strata apartment complex on 10th Avenue and Market Street at about 5:45 a.m. Monday, SDPD officer Dino Delimitros said.

Inside a unit on the fourth floor of the high-rise complex, officers found a person with at least one gunshot wound.

A witness said he saw medics placing gauze on a man's head as they rushed him out of the complex at the UCSD Medical Center in Hillcrest. Police later said the victim's gunshot wound was to his upper body and that his injuries are life-threatening.

Several people who were at the gathering were detained for questioning but a suspect was not in custody at 11 a.m., SDPD said.

Officers were locking down the area for an investigation into the shooting.

At 6:30 a.m., Market Street between 9th and 10th avenues was shut down in both directions and a Sig Alert was issued for several hours.

No other information was available.

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