One Kenmore-Town of Tonawanda school bus was destroyed and two others damaged in an early-morning fire Monday at the school bus lot on Military Road, Town of Tonawanda police reported.

Volunteer firefighters from the Sheridan Park Fire Co. responded to a 1 a.m. alarm at the fenced-in lot at 1680 Military Road, police said. The blaze destroyed Bus 380 and left smoke and heat damage to Buses 379 and 381.

Authorities are eyeing a possible electrical cause.

“At this point in the investigation, it does not look to be arson,” Town of Tonawanda Police Lt. Nicholas A. Bado said. “We’re not ruling anything out, but the main culprit appears to be block heaters that are plugged into the bus engines.”