WELLSTON — A police officer was fatally shot Sunday afternoon while answering a call about a customer trying to cash a bad check at Clay’s Wellston Food Market Restaurant, North County Police Cooperative Chief John Buchannan confirmed.

The officer has been identified as Michael Langsdorf, 40, who had worked for the cooperative for three months.

A suspect is in custody and a gun has been recovered, Buchannan said outside Barnes-Jewish Hospital, where Langsdorf had been taken after the shooting.

Langsdorf was called to the market, 6250 Page Avenue, around 4:30 p.m. to investigate a bad check complaint, Buchannan said. About 5 minutes later, a radio call went out for an officer down.

The person who tried to cash a bad check is the suspect in the shooting, police said.

Most of the confrontation was caught by a store surveillance camera near the counter. It showed that the encounter lasted 1 minute, 16 seconds, according to a source familiar with the investigation.

The source described the footage: