MCKINLEY PARK — A vacant warehouse that caught fire earlier this week, triggering the largest blaze in the city in nearly a decade, is being investigated as a possible arson, authorities said Friday.
Chicago Police officer Veejay Zala, a police spokesman, said Friday afternoon that officials were investigating whether the fire was intentionally set.
Fire department spokesman Larry Langford said his department determined the fire was not ignited by "natural causes." He said the fire started on the second or third floor, but said the materials that started it were unknown.
"You've got a building standing empty like that with no utilities and nothing in there that could start a fire on its own from natural causes," he said. "That leaves that you had to have a flame source from someplace. ... How it got there and why it got there would make an accident or arson."
What happened will be determined by the police, which now have the case, Langford said.
Earlier Friday, crews started demolishing the building.
In a Twitter update sent about 11:15 a.m., the Fire Department said they would demolish the huge warehouse in the 3700 block of South Ashland Avenue.
Working at the southwest corner of the warehouse, teardown crews used a crane with an attached grabber to take bites out of the building's top-floor brick-and-ice skeleton, piece by piece.
Fire crews continued to douse the building's wrecked interior, where a brownish-grey smoke continued to lift into the sky.
The ongoing demolition continues to draw neighbors, news crews and amateur photographers, some who said the spectacular blaze, the ensuing "ice palace" and demolition was a once-in-a-lifetime event.
That's what brought Edwyn Jenkins to the scene. Jenkins, 53, of Humboldt Park, said he came to see the teardown, which he said carried its own sort of eerie beauty.
"It's pretty really," he said. "As long as nobody got hurt."
The initial blaze Tuesday night was fought by 200 firefighters. It was the city's biggest blaze since Dec. 6, 2004, when the LaSalle Bank headquarters at 135 S. LaSalle St. caught fire.
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Large clouds of smoke could be seen from about half a mile away as trucks blasted water on Thursday.
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Construction crews began their teardown of a still-burning Bridgeport warehouse on Friday
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Firefighters work to extinguish a massive blaze at a vacant warehouse on Wednesday in Chicago, Illinois. More than 200 firefighters battled a five-alarm fire as temperatures were in the single digits.
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Firefighters work to extinguish fire that reignited in a vacant Bridgeport warehouse Thursday.
DNAinfo/Geoff Ziezulewicz
A massive fire that engulfed a vacant warehouse in Bridgeport reignited Thursday morning.
DNAinfo/Geoff Ziezulewicz
Five-alarm response required for massive blaze at Bridgeport warehouse.
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Water from multiple fire hoses appeared to freeze almost on impact.
DNAinfo/Casey Cora
Dozens of onlookers gathered to watch crews battle a five-alarm warehouse blaze.
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A firefighter douses a massive warehouse fire with water.
DNAinfo/Casey Cora
Firefighters work to extinguish a massive blaze at a vacant warehouse Wednesday. More than 200 firefighters battled a five-alarm fire as temperatures were in the single digits.
Scott Olson/Getty Images
Firefighters work to extinguish a massive blaze at a vacant warehouse Wednesday. More than 200 firefighters battled a five-alarm fire as temperatures were in the single digits.
Scott Olson/Getty Images
Firefighters work to extinguish a massive blaze at a vacant warehouse Wednesday. More than 200 firefighters battled a five-alarm fire as temperatures were in the single digits.
Scott Olson/Getty Images
Firefighters work to extinguish a massive blaze at a vacant warehouse Wednesday. More than 200 firefighters battled a five-alarm fire as temperatures were in the single digits.
Scott Olson/Getty Images
Firefighters work to extinguish a massive blaze at a vacant warehouse Wednesday. More than 200 firefighters battled a five-alarm fire as temperatures were in the single digits.
Scott Olson/Getty Images
A frozen, burned out warehouse on South Ashland Avenue in Bridgeport, taken hours after the massive fire.
Chicago Fire Department
Firefighters work to extinguish a massive blaze at a vacant warehouse Wednesday. More than 200 firefighters battled a five-alarm fire as temperatures were in the single digits.
Scott Olson/Getty Images
Firefighters work to extinguish a massive blaze at a vacant warehouse Wednesday. More than 200 firefighters battled a five-alarm fire as temperatures were in the single digits.
Scott Olson/Getty Images
Firefighters work to extinguish a massive blaze at a vacant warehouse Wednesday. More than 200 firefighters battled a five-alarm fire as temperatures were in the single digits.
Scott Olson/Getty Images
Firefighters work to extinguish a massive blaze at a vacant warehouse Wednesday. More than 200 firefighters battled a five-alarm fire as temperatures were in the single digits.
Scott Olson/Getty Images
Firefighters work to extinguish a massive blaze at a vacant warehouse Wednesday. More than 200 firefighters battled a five-alarm fire as temperatures were in the single digits.
Scott Olson/Getty Images
The fire department brought out this decades-old deluge unit to blast water on the warehouse Thursday. The truck is rarely used, but still works to put out flames, the fire department said
Chicago Fire Department
This rare deluge unit was brought out to pour water on the warehouse Thursday morning. The Chicago Fire Department said this deluge was from either 1969 or 1970
Chicago Fire Department
Firefighters work to extinguish a massive blaze at a vacant warehouse Wednesday. More than 200 firefighters battled a five-alarm fire as temperatures were in the single digits.
Scott Olson/Getty Images
Firefighters work to extinguish a massive blaze at a vacant warehouse Wednesday. More than 200 firefighters battled a five-alarm fire as temperatures were in the single digits.
Scott Olson/Getty Images
Firefighters work to extinguish a massive blaze at a vacant warehouse Wednesday. More than 200 firefighters battled a five-alarm fire as temperatures were in the single digits.
Scott Olson/Getty Images
Firefighters continue to pour water on a warehouse in Bridgeport the morning after the South Ashland Avenue building was engulfed in flames.
DNAinfo/Geoff Ziezulewiscz
Firefighters work to extinguish a massive blaze at a vacant warehouse Wednesday. More than 200 firefighters battled a five-alarm fire as temperatures were in the single digits.
Scott Olson/Getty Images
Firefighters get ready to blast the South Ashland Avenue warehouse on Thursday, when the fire department said a fire rekindled in the building.
DNAinfo/Geoff Ziezulewiscz
Firefighters douse the South Ashland Avenue warehouse with water Thursday morning.
DNAinfo/Geoff Ziezulewiscz
A firefighter works at the warehouse on South Ashland Avenue Thursday morning, after the building once again caught on fire. It first erupted in flame Tuesday night
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The trucks blasted water at a rate of 2,500 gallons per minute, firefighters said Thursday.
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Firefighters blast water on the warehouse on South Ashland Avenue on Thursday after the fire rekindled about two and a half days later.
DNAinfo/Geoff Ziezulewiscz
Trucks blast water on the icy warehouses 3757 and 3801 S. Ashland Ave. Thursday morning.
DNAinfo/Geoff Ziezulewiscz
Large clouds of smoke could be seen from about half a mile away as trucks blasted water on Thursday.
Photo Credit: DNAinfo/Geoff Ziezulewiscz
The huge effort left behind an ice palace. The fire, however, was rekindled again Thursday.
The fire department brought out a vintage deluge unit made in 1969 or 1970. Firefighters said trucks blasted 2,500 gallons of water per minute trying to douse out the flames.
As the demolition was underway Friday, the Fire Department sent a tweet at 4:31 p.m. saying the fire was caused by “open flame ignition of available combustibles. The case has now been passed to the Chicago Police Department."
Langford said that technically means "something that was burning got near something that could burn."
The warehouse is owned by a developer whose bribery attempts landed him and a former West Side alderman in prison, records show.
Calvin Boender, 58, listed on state documents as the president of North Development Ltd., owns the vacant warehouse at 3757 S. Ashland Ave.
Boender was caught in a bribery scandal that put former Ald. Isaac “Ike” Carothers (29th) behind bars.
Calvin Boender, who is serving time for bribing public officials, is the owner of a Bridgeport warehouse that burned and...