BRIDGEPORT -- What began as a string of Christmas Eve arsons in the Hollow turned into a homicide investigation after firefighters found the body of a man inside a burning home on Madison Court.

Firefighters found the body in a second-floor apartment while battling the blaze, which began just after 3 p.m. in 6 Madison Court.

The 2 1/2-story home is on a small side street off Madison Avenue, near its intersection with North Avenue and Grand Street.

The stubborn blaze was still burning at 6:15 p.m. Monday, prohibiting arson investigators and police detectives from entering the building and American Medical Response technicians from removing the body. A gurney was readied outside the home.

The police crime van also was dispatched to the scene while Public Works employees blocked Madison Avenue to through traffic between Madison Court and North Avenue.

Fire officials believe the man was living illegally in the home as a squatter.

It was one of three vacant buildings set on fire in little more than an hour and within seven blocks of each other.

At 9:34 p.m., the Bridgeport Fire Department was called back to the same area for yet another fire in a vacant house, this one on George Street. When firefighters arrived, the house, described as a 21/2-story, four-family, was fully engulfed.

With firefighters still on the scene, there was no word whether the nighttime fire might be related to the others.

The blazes occurred the same day that two firefighters were fatally shot in a suburb of Rochester, N.Y., by a man who had set a house and car on fire in his neighborhood.

In the Bridgeport fires, police are seeking a man, described as in his 50s and wearing blue clothes, who witnesses claim they saw running from a fire at 325 Center St.

The Center Street home was the second of three vacant homes set ablaze. Investigators suspect the three fires were set by the same person or people.

With so many buildings burning so close together and at the same time, firefighting help was summoned from Easton, Fairfield, Shelton, Stratford and Trumbull.

The first fire started at 1:45 p.m. in 359 Olive St., a 2 1/2-story wood-frame home. Firefighters battling that blaze received a call 13 minutes later that the 1 1/2-story home on Center was burning.

While crews were still working those two fires, a call came in at 3:06 p.m. reporting the Madison Court blaze.

"This is scary," said Crystal Pedreira, who was at the Madison Court fire and also the Center Street house. "A lot of homeless people sleep in these vacant buildings."

The houses are just blocks from each other. Angel DeJesus also saw both fires.

"Just 10 minutes after they put out Center Street, this building went up," he said of the Madison Court fire. He, too, said homeless people had been staying there.

While firefighters were attempting to extinguish the Madison Court fire, the Olive Street house went up again.

"Oh my God, this is crazy," said Jose Villafane, who lives on Coleman Street and saw the two-story Olive Street home go up twice Monday. "It's unbelievable -- on Christmas Eve yet. Thank God no one was living there."

Villafane said the owner had been fixing the home.

Bill Kaempffer, the city's police and fire spokesman, said fire officials told him they pumped "a lot of water" on the first Olive Street fire.

"They believe it wasn't a rekindle, it was a relight," he said.

Because so many Bridgeport firefighters were tied up on Center Street and with the gruesome discovery on Madison Court, Fairfield fire officials were the first to respond to the second fire at Olive Street. While they were there, the rear of the building began burning so heavily it melted siding onto adjacent homes.

If that wasn't enough, a predawn fire destroyed a one-story industrial building on Knowlton Street.

Six engine and three ladder companies responded to the 3 a.m. blaze at 33 Knowlton St., which housed a woodworking company. Although some units were recalled at 7 a.m., a number of firefighters were on the scene all day.

Investigators from the state Department of Energy and Environmental Protection were called to the scene.

"It's a woodworking and finishing company of some kind, so there are paints and solvents, things like that," Assistant West Side Chief Robert Morton said.

Morton said the blaze began in the basement and quickly spread, collapsing the roof.

A firefighter injured his back and was taken to Bridgeport Hospital, where he was treated and released.

The 12,000-square-foot building, constructed in 1930, is owned by S.B. Associates, city records show. One company doing business there was the Pequonnock River Woodworking Co.

Staff writers John Burgeson and Tom Cleary contributed to this report., 203-330-6286;