Two men were charged Saturday in connection with the fatal shooting, Dec. 29, of an off-duty Chicago police officer, the Chicago Tribune reported.

Bail was denied for Tyrone Clay, 29, and Edgardo Colon, 34, both of Chicago, during bond hearings Saturday. They were charged with murder while in commission of a forcible felony and first-degree murder of a peace officer, according to a statement from Chicago Police News Affairs.

Officer Clifton Lewis, 41, was shot during a robbery of M&M Quick Foods in the 1200 block of North Austin Boulevard, where he worked a second job as a security guard. Lewis was an eight-year veteran of the department and was assigned to the 15th District Tactical Team.

Colon confessed he was the driver during the attack, while Clay and a third man entered the store with masks on, the Tribune reported. Lewis announced he was a police officer, and Clay and the third man opened fire. Lewis fired one shot before he was struck in the abdomen and back. Bullet fragments also struck a store employee.

Clay took about $670 from the cash register while the other man took Lewis’ gun before they fled to the waiting car, according to the Tribune.

According to court documents, a fourth person who worked on planning the robbery was in the car when all four drove to the store.

Chicago Police Department Superintendent Garry McCarthy said at a press conference Saturday that police were “not even close” to being done with the investigation, according to the Tribune.