CHICAGO (CBS) — The Police Board on Thursday approved a six-month suspension for a sergeant who shot an unarmed teenager with disabilities.

Early on Aug. 13, 2017, Sgt. Khalil Muhammad shot Ricardo Hayes, then 18, in the arm and chest on the 11100 block of South Hermosa Avenue in Morgan Park.

Hayes, who is developmentally disabled, had a history of sneaking out of his home, according to a detailed account of the incident published by The Intercept.

In the surveillance video from the front porch of a residence, Hayes is seen running to the left of the screen. He stops as a vehicle pulls up, and shots ring out moments later.

Muhammad told investigators he was off duty and wearing civilian clothes when he saw a suspicious man, Hayes, near his neighbor’s car.

Muhammad said he identified himself as an officer and asked Hayes what he was doing.

Then told him he needed to see his hands.

Then he said Hayes turned toward him, reached back and started to pull a dark object off his waistband.

That’s when Muhammad fired his semi-automatic pistol at Hayes, claiming he feared for his life while still in the front seat of his girlfriend’s sport-utility vehicle.

The Civilian Office of Police Accountability completed its investigation of the shooting in September. COPA called Sergeant Muhammad’s actions “objectively unreasonable” but did not recommend his termination.

Instead COPA initially recommended a 90-day suspension. In March, it recommended doubling the suspension after meeting with then-police Supt. Eddie Johnson.

The Police Board on Thursday approved the 180-day suspension for Muhammad.