A vacant office building caught fire early Sunday morning in the 100 block of Elm Street, fire investigators said.

At about 6:30 a.m., a man on his way to work called in the fire while driving by the vacant building, 141 E. Elm Street. After arriving, Sycamore firefighters found white smoke coming from the sides of the building, according to a Sycamore Fire Department news release.

After entering, firefighters found the origin of the fire inside a room of the west side of the building, according to the release. The fire was extinguished within 20 minutes, and firefighters remained on the scene for about two hours after to remove smoke. An estimated $60,000 in damage was reported to the structure and $1,000 to its contents, according to the release.

Sycamore Fire Chief Bill Riddle said the fire was ruled accidental, and believed to be caused by electrical equipment wiring.

No firefighters were injured.