Naperville police released video of the incident, showing an officer shoot a man, who ran at him with a hatchet.
The shooting occurred on June 3 during a traffic stop, near Bond Street and McDowell Road.
The video shows another car pull up, and a man get out and immediately charge at the officer with a hatchet in his hand. The officer then opened fire.
RELATED: Naperville police shooting: Man shot, killed after allegedly attacking officer with hatchet ID'd
The man, identified as 28-year-old Edward Samaan, died at a hospital. The officer was not hurt.
WATCH | Chopper7 over Naperville police shooting scene
Naperville police fatally shoot man who allegedly attacked officer with hatchet
The state's attorney's office said the officer reasonably believed the man was trying to kill him or the subject of the traffic stop.
No criminal charges will be filed against the officer.
The state's attorney's office said Samaan was shot five times.
The officer involved said he "had a crazed look in his eyes."