SAN DIEGO - Workers at a San Diego auto-repair shop arrived at work to find that a five-gallon bucket of cleaning solution had fallen off a military aircraft and crashed through the roof of the business, damaging a half-dozen cars.

Military officials said the container of solvent had fallen out of an MV-22 Osprey tiltroter.

The bucket plunged onto an unoccupied building, where it broke open and spewed its contents on about six vehicles.

The container apparently had been tied down aboard the aircraft, but somehow came loose and slid out a hatch or other opening, officials said.

A hazardous materials team was called in, but the cleaning solution was water-based and most of it had evaporated and there was no danger lingering.