A raging fire in the St. Roch neighborhood destroyed one house Wednesday morning and left two more slated for demolition. Neighbors said the blaze started in an abandoned house frequented by squatters.

The Fire Department said no injuries were reported. The cause of the fire is under investigation.

The house where the fire began, a wood-frame duplex at 1623-25 Marigny St., collapsed as a result of the blaze. A bus and a camper parked on an empty lot next door also were destroyed.

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Neighbor Tasha Brock said she heard a series of loud pops about 9 a.m. and worried at first that someone was firing a gun. A man was shot to death on the block earlier this month.

“It sounded like somebody was shooting out here,” Brock said. “It was popping.”

Fire Superintendent Tim McConnell said that after the department received a 911 call, a passing hazardous materials officer spotted the fire about 9:08 a.m. and alerted a woman in one of the adjacent houses who hadn’t realized what was going on.

He said firefighters were on the scene within five minutes and had it under control in less than an hour.

Valerie Butler Polk, who lives two doors down from the collapsed house, said she was ironing clothes when she heard the initial pops. “I ran around in three circles trying to figure out what to do,” she said.

Polk, 55, then managed to collect her wits, move her car and carry her 7-year-old German shepherd, King Zeus, to safety. She was still wearing a brightly colored bathrobe as she watched firefighters dousing the flames.

Polk said the house where the fire started was regularly used by squatters but that her calls to the city had gone unheeded.

Another neighbor complained of frequent drug use at the residence.

McConnell said the fire appeared to be “another example of a property owner not taking care of their property. ... The same situation in the middle of the night — it could have been much, much worse.”

The building at 1623-25 Marigny was given a blight judgment in July, according to City Hall spokesman Hayne Rainey, and the city recommended it for sale.

But it was not immediately clear who owns the building. Assessor’s Office records list the property as belonging to a company called VJW Properties, but one of the company’s agents said the residence was surrendered at bankruptcy in 2014.

Bryan Lagarde, who maintains a network of surveillance cameras through the anti-crime organization ProjectNOLA, said he spotted “suspicious activity” on video at the residence just before the fire was discovered. He declined to say what that activity was, but he said he had referred the footage to Fire Department arson investigators.

Whatever the cause of the fire, its spread meant that two additional residential buildings will be demolished. Rainey said that 1617-19 Marigny and 1631-33 Marigny will have to be leveled because of damage from the fire.

The first building was occupied, Rainey said, but the other building already had a pending application for demolition with the Neighborhood Conservation District Advisory Committee.

While the first engine to arrive on the scene got there within five minutes, efforts to contain the blaze may have been hampered because fire companies in the 3rd District, which covers the swath of neighborhoods from Marigny to the Lower 9th Ward and extends through Gentilly to the lakefront, had been assigned to additional duties Wednesday.

All 3rd District companies were sent to the Stallings St. Claude Recreation Center on Lesseps Street to aid city Mosquito Control Board crews working to eliminate standing water in containers as part of the city’s effort to fight the Zika virus, according to a memo sent to district officials Tuesday night. Those companies remained on duty but were far from their home stations.

Among the units on that temporary assignment was Engine 27, normally based at the station at Interstate 10 and Elysian Fields Avenue, just blocks away from Wednesday’s fire. But it took that engine more than 20 minutes to arrive at the scene, in part because it was stuck behind a mosquito control truck, said Nick Felton, president of the firefighters union.

Such additional duties for firefighters are not new but appear to be becoming increasingly common, said Felton, who noted that other units in the city were assigned to fill pools at recreation facilities on Wednesday.

“There’s no way to prevent the fire, but I truly believe that this fire could have been prevented from spreading to adjacent structures and could have been contained to a couple rooms had we had the proper response,” Felton said.

In order to prevent problems with traffic or other issues, the department dispatches four engines at a time to fires, as happened Wednesday, Fire Department spokesman Michael Williams said.

The fire came less than a year after an Aug. 7 blaze in the next block of Marigny Street that firefighters deemed suspicious. That fire happened the same evening as another suspicious fire in the 2000 block of North Derbigny Street in the 7th Ward.

McConnell said Wednesday it was too early to tell if there were any connections between those fires and the latest blaze.

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