AURORA, Colo. (AP) — A 17-year-old boy was fatally shot while exchanging gunfire with a former police officer in suburban Denver Wednesday night, police said.

Investigators believe the shooting happened after the 36-year-old former officer got into an argument with a group of teens over careless driving in a residential neighborhood in Aurora, police said. Sometime during the argument, both the 17-year-old and the former officer pulled out guns and fired shots at each other, police said.

The former officer was also shot but was expected to survive, police said.

The name of the former officer was not released but police said he used to work for the police department in Greenwood Village, another Denver suburb.

No arrests have been made. Detectives were working to determine who the primary aggressor was, police said.