The Boston Fire Department reports that shortly after 6:30 p.m., a utility pole at Gerard and Kemble streets could stand gravity no longer and cracked, the high-voltage transformer at the top plunging to the ground, turning a nearby car and a street-sign pole into electrical conduits and disgorging its insulating mineral oil all over the place.

Eversource and a company that specializes in hazardous-waste cleanups were called in.