ANTWERP — A fire of unknown origin destroyed a three-story building in the village's downtown early Sunday.

The fire in the vacant apartment building at 62 Main St. was "fully involved, with flames showing" by the time Antwerp Fire Department arrived about 5 a.m., according to first assistant Chief Christopher M. Sands.

"Nobody went in," Mr. Sands said. "We concentrated on trying to save the other buildings."

An adjacent building on the south side at 64 Main St. sustained no damage, while a building on the north side at 60 Main St. sustained fire damage to its roof and upper floors. The village police department is two doors down from the burned building, with village offices in the same building at 58 Main St.

Jefferson County code enforcement officials condemned 62 Main St. and 60 Main St. and ordered the burned building torn down, Mr. Sands said. Firefighters remained at the scene until about 5 p.m. as the demolition occurred.

No one was injured in the fire. Power was shut off to the downtown area most of the day Sunday.

Mr. Sands said he believed the apartment building was empty. He was unsure if it had power going to it at the time of the fire.

A state police K-9 unit was brought to the scene to assist in finding the cause of the fire. County fire investigators, who could not be reached for comment Sunday evening, are leading the search for the cause.

Antwerp Fire Department was assisted at the scene by departments from Philadelphia, Oxbow, Gouverneur, Theresa, Evans Mills, Pamelia, Brown-ville, Great Bend and Fort Drum, as well as Thousand Islands Emergency Rescue Service. Several departments were also placed on stand-by.