NEW SEWICKLEY TWP., Pa. -- A fire in a trash compactor caused damage to a Beaver County mailing service.

It started at around 11:20 p.m. Monday at Pittsburgh Mailing Services in New Sewickley Township. The company is a bulk mailing service.

Investigators said an employee spotted the fire, which was on the outside of the building. Five fire companies responded to the scene, and the flames were under control in about 20 minutes.

Smoke got into the building, and the employees were evacuated. No one was hurt. Everyone was allowed back inside once the building was vented.

Investigators still don't know what caused the fire, but they said it is not suspicious. They said they plan to return to the building Tuesday afternoon to try to find out what caused the trash compactor to ignite.