'Safe to Say It was Arson': ATF Helping with Probe into Pa. Police Vehicle Fires

The ATF is assisting with an investigation of a suspicious fire Wednesday in a parking lot outside a Pennsylvania police station.

Four Mckeesport police vehicles were damaged in a fire that broke out at around 3:15 a.m. in a parking lot next to the police and fire stations, KDKA-TV reports. The lot has no security cameras, and investigators are checking if surrounding surveillance cameras in the area caught anything.

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"I think it's safe to say that it was arson," said Mayor Michael Cherepka during a press conference.

Police K-9 units and fire department investigators have looked over the lot. At least one ATF agent also was investigating the scene Wednesday.

"Obviously, this is an attack on police," said Cherepka. "And the one thing we are very grateful for is that there were no injuries."

A $5,000 reward is being offered by the ATF for information leading to an arrest in the case.