A popular, high-ranking commander in the Chicago Police Department was shot and killed Tuesday afternoon, as he was assisting other officers in chasing a suspect.

Commander Paul Bauer, of the 18th District, was shot multiple times, said Police Superintendent Eddie Johnson in a press conference later Tuesday.

Fox News reported:

Johnson stated that earlier Tuesday afternoon, Chicago police saw someone “acting suspiciously” who quickly fled from the tactical officers. A description of the suspect was broadcast on police radio, and when Bauer, who was off-duty, saw the offender, he reportedly approached the individual.

The superintendent said that while “any loss of life in this city is tragic, today is difficult.”

After the shooting, Bauer was transported to Northwestern Memorial Hospital. Fox 32 Chicago reported the commander was shot in a stairwell of the Thompson Center in the city’s downtown business center.

Sources told Fox News that police seemed to be responding to a robbery, and the fallen officer was shot as he chased the suspect.

Bauer was a 31-year veteran of the department, and was previously the commander of the department’s mounted patrol unit. He leaves behind a wife and daughter.

The Chicago Sun Times reported:

He was in charge of the mounted unit in 2013 when the Blackhawks won the Stanley Cup. Officers on 30 horses kept control of the streets in Wrigleyville after people broke down police barricades.

Bauer was involved with the Chicago Police Memorial Foundation, which assists the families of fallen and injured officers.

He helped with the Horses of Honor project, in which 6-foot-tall, 6-foot-long horse statues were displayed downtown. Each horse, decorated by local artists, carried a minimum donation of $2,500 for the foundation.

All but one of the horses was named after officers who died.

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