CHICAGO (CBS) — There were questions late Sunday after a Chicago Police sergeant was shot and wounded in broad daylight outside the Gresham District police station.

The officer was already out of the hospital by late Sunday night. But CBS 2’s Steven Graves was trying to figure out how such a thing happened in the first place.

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The outside of the Gresham (6th) District police station, 7808 S. Halsted St., turned into the scene of a massive investigation Sunday afternoon.

SWAT teams and police K-9s were searching near the station – with officers knocking on home doors and combing through alleys.

Many people were confused as to why.

“When the cop cars started lining up here, I started noticing. I’m like, ‘What’s going on?’” said store manager Tiwfek Salah. “I was taking care of a customer.”

Salah did not hear anything. His shop is feet from the station’s parking lot.

That was where at 2:33 p.m., Chicago Police said a sergeant was standing when he heard a gunshot, and then felt pain – a graze wound to the chin.

Police late Sunday said they were looking at multiple cameras for clues – video from the police station, pod camera video, and closed-circuit television video nearby.

There were no details on the search for a suspect given at an afternoon news conference.

“None of the evidence that we’ve so far heard from the officer, the sergeant, or others that heard the shot have any additional information we can corroborate,” police Supt. David Brown said at the news conference.

Brown used this as an opportunity to highlight that more than a dozen officers have been shot at in the city so far this year.

Police said the sergeant is a 26-year-veteran of the CPD and is assigned to the Gresham District. The sergeant has received of 127 departmental awards including 13 department commendations, nine complimentary letters, and 73 honorable mentions, police said.

Brown said last year, 79 officers were fired upon and 10 of them were struck, and this year, the figures are at pace for an even greater total. So far since Jan. 1, 13 officers have been shot at and the sergeant is the first to be struck, Brown said.

“Our officers display an enormous level of resiliency and put themselves in harm’s way each and every day, whether it’s responding to a call or simply standing in their own parking lot,” Brown said in part in a tweet Sunday afternoon.

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The sergeant only spent about five hours in the hospital at Advocate Christ Medical Center in Oak Lawn. Supt. Brown said the sergeant was in good spirits.

CBS 2 Chicago Staff