A Denver Police Department officer shot a person who police say fired at officers at an apartment complex early Saturday.

The shooting happened just before 2 a.m. in the 4300 block of South Quebec Street. Denver Police Chief Ron Thomas said at a news briefing that officers were called on reports of an armed confrontation, which he said was possibly a carjacking.

After arriving on scene, officers spoke with a witness who pointed police in the direction of the incident, where they found a man matching the description of the suspect. Thomas said officers “challenged” the suspect, who fired at officers.

Thomas said the officers returned fire, with one officer striking the man with rounds from a rifle. He went down, Thomas said, and officers began performing life-saving measures on the suspect until an ambulance could arrive to transport him to a hospital.

Thomas said as of 4 a.m. the suspect was in critical condition, but police said at about 12:20 p.m. that he had died. The man’s identity will be confirmed and released by the Denver Office of the Medical Examiner.

None of the officers were injured.

The incident is under investigation by the department’s homicide unit, the Colorado State Patrol and the Colorado Bureau of Investigation, Thomas said.