The federal bureau of Alcohol, Tobacco, Firearms and Explosives said it's assisting in the investigation of an apparent pipe-bomb explosion that damaged a police vehicle in the western Maryland town of Thurmont.

The Frederick News-Post reported that the incident occurred early Wednesday in the town of 6,100 about 70 miles northwest of Baltimore.

Thurmont Police Chief Greg Eyler said an explosive device damaged the hood and windshield of an SUV parked on the street outside an officer's home. Eyler said no one was hurt.

ATF spokesman David Cheplak said ATF agents responded to the scene.

Eyler said investigators collected evidence that will be analyzed at an ATF laboratory in Beltsville.