SAN FRANCISCO (CBS SF) — A San Francisco police officer is in critical but stable condition after an exchange of gunfire with a suspect in the city’s Castro District early Wednesday morning, police said.

Just a few minutes after midnight, a citizen flagged down officers regarding what was described as a suspicious vehicle near 18th and Collingwood streets, according to police.

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“As the officers approached the vehicle to investigate, there was an exchange of gunfire between the suspect and at least one officer,” said SFPD Sgt. Michael Andraychak.

Authorities on the scene after an officer-involved shooting in San Francisco's Castro District on November 1, 2017. (CBS)

Authorities on the scene after an officer-involved shooting in San Francisco’s Castro District on November 1, 2017. (CBS)

One officer, a 41-year-old man who is a nine-year veteran of the department and is assigned to the Crime Scene Investigation Unit, was taken to a hospital with a gunshot wound, according to police.

Police said the officer normally works CSI, but was assigned to foot patrol Tuesday night as extra coverage because it was Halloween.

The suspect was also taken to a hospital with life-threatening gunshot wounds, police said. His name has not been released.

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Officers recovered a firearm at the scene that is believed to belong to the suspect.

Investigators determined that the suspicious vehicle was a gray Chrysler sedan that had been reported stolen.

Police are also investigating whether the carjacking theft of a taxi shortly after the shooting has any connection to the case.

The case is being investigated by the Police Department’s homicide detail and internal affairs division, the San Francisco District Attorney’s Office, and the Department of Police Accountability.

Police said they plan to hold a town hall meeting about the case within the next 10 days.

Anyone with information about the case is asked to call the San Francisco police tip line at (415) 575-4444, or to text a tip to TIP411 and begin the message with “SFPD.” Calls and texts can remain anonymous.

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