A mechanic shot and killed one co-worker and critically injured another before police killed the gunman at a Metropolitan Transit System bus complex in downtown San Diego, authorities said.

A report came in around 2:15 a.m. Tuesday saying two people had been shot at the complex in the East Village area near Petco Park, police Sgt. Bob Dare said. The gunman was shot by police shortly after they arrived at the bus yard.

The shooter was identified as a mechanic on automated bus fare boxes who had worked for MTS for about 30 years, agency spokesman Rob Schupp said.

The injured man, a bus mechanic who also was a 30-year veteran, was in critical condition at a hospital. The employee who was killed had been a foreman for about four years, Schupp said.

No names were released. The motive for the shooting was under investigation.

About 10 people were working at the bus depot at the time of the shooting, according to an MTS spokesman. Bus delays ranged from 10 minutes to a half-hour.

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