Philadelphia police said someone set several police cars on fire early Monday morning in West Philadelphia.
The police cars were empty; no one was hurt and the small fires were quickly extinguished. However, the fires damaged at least five police cruisers, police at the scene said.
In one case, it appeared a device was put in the wheel well of a car. In another, a flammable liquid appeared to have been poured on the car.
The fires happened at several locations in West Philadelphia, including 40th and Chestnut streets, 7th and Chestnut and 39th and Lancaster.
There is no description of the suspect, but the locations are heavily traveled streets with many businesses that may have surveillance cameras.
Police are being urged to keep their cruisers in sight.
For more on this story visit NBC Philadelphia.