Two undercover officers with the Atlanta (GA) Police Department were investigating a complaint of drug activity when shots were fired at their unmarked patrol car on Monday, according to the Atlanta Journal-Constitution.

Captain Reginald Moorman told Channel 2 News that the officers saw the suspect pull out a rifle: "At that point, he started firing at the officers. The officers were not able to return fire. They actually removed themselves from the situation and called for additional units."

Several rounds struck the vehicle, but the officers were unhurt.

A standoff subsequently ensued.

Police eventually detained a total of six people and arrested one on an outstanding warrant for something unrelated to the shooting, according to WSB-TV.

Investigators are still trying to determine who was the shooter or if that person got away.