A suspicious fire early this morning tore through a vacant, three-story house on East Fulton Street in Butler, forcing concerned neighbors from their own homes and into cold temperatures outside.

City firefighters for more than two hours battled the stubborn blaze reported about 3:30 a.m. The fire gutted the house but firefighters using foam and water managed to keep the flames from other homes precariously close by.

Cpl. Jeff Crede, state police fire marshal in Butler, was to begin an investigation this morning.

"Since there's been no one residing in the house for years and no utilities there,"said Butler police Chief Tim Fennell, "there's reason to believe we're looking for an arsonist."

The gutted house at 403 E. Fulton St. has remained empty for eight to 10 years, and has been more than just an eyesore to neighbors.

"It's been a problem for a long time," said Andy Kappler, who lives below the house that sits on a hillside between Oak and North Monroe streets.

"We believe it's been a drug house and that people are doing drugs and sleeping in there," he said. "It's a helluva thing to wake up to but I've been waiting for something like this."

Several neighbors said they have informed police and city officials of their concerns over the years; some have reported seeing the occasional person going into the house.

Police were last called to the house on Sept. 26, after a neighbor reported seeing an open door.

"We looked around and there was indication that someone may have been hanging around in there,"Fennell said.

Knowing that the house could have been recently used by a squatter or trespasser, first-arriving fire crews were alerted of the possibility that someone could be trapped inside.

William Pratt of Rockford, Ill., owns the house, according to authorities. He could not be reached for comment this morning.

Fennell said police spoke by telephone with Pratt on Sept. 26 and "asked him to board (the house) up."

Pratt told police he would hire a contractor; however, no timetable was set and no action taken.

Meanwhile, Kappler credited his Weimaraner and mixed breed dogs for saving him and his family.

"Their barking woke us up,"he said. "That's unusual for them; like us, they're normally sleeping at this time."

Kappler peered out the bedroom window and spotted the large three-story house — just above his own home — on fire.

"It was real bright back here,"he said. "The flames were shooting out the first-floor windows."

The Kappler family was getting out of their house when neighbor John Walchesky knocked on their door, just in case they didn't know what was going on outside.

Walchesky, who lives on Oak Street, had already called in the fire to 911 dispatchers.

Kappler, meanwhile, quickly joined in the emergency wake-up service around the neighborhood.

"I was sleeping. Ididn't hear a thing,"said Jim Grossman; that is until Kappler, his next-door neighbor, roused him with repeated bangs on the door.

"This place was totally engulfed in the back,"Grossman said, looking at the house on fire about 30 minutes after his sleep was interrupted. "I was totally amazed."

Kappler's and Grossman's homes sit just 10 feet or so below the burning house. Both men were worried that the fire could spread to their homes.

Firefighters laid hose lines from Oak Street down to the house and sprayed it heavily with water and foam. But just when it seemed the flames were out, another hot spot appeared, primarily on the first or second floor.