A police squad car caught fire this afternoon as two officers were traveling on Loop 12 in Dallas near Cockrell Hill, authorities said.

Officers inside the Dodge Intrepid with an AR-15 in the trunk were not injured in the incident which began about 1:30 p.m. near Jefferson Boulevard, Dallas police said.

The officers had gotten out of their car after smelling something and noticed flames, said Dallas Fire-Rescue spokesman Ernest Gurule. The officers got a safe distance from the vehicle and began directing traffic away from the fire.

Firefighters let the car burn itself out because officials feared ammunition in the vehicle would explode and send shrapnel into the air and injure personnel, Gurule said. An officer said he could hear the rounds of ammunition exploding in the fire.

The catalytic converter in the vehicle appears to have caught on fire, Dallas fire said. It was likely that some foreign substance - either paper or plastic - somehow made contact with the hot converter and caught fire.

The road, which was closed earlier this afternoon between Keeneland Parkway and Jefferson Boulevard, reopened about 4 p.m., according to Traffic Pulse.