A property owner is facing violations for illegal gas work following a Bronx explosion Thursday that injured multiple people, authorities say.

Nine people and a firefighter were in the explosion Thursday afternoon at a Westchester Square building. Multiple children were among the injured, including two who were hurt critically.

The explosion on Paulding Avenue was so powerful that the windows of the building were completely blown out. The blast also left a door hanging from a power line after being blasted from an apartment.

The FDNY says the explosion happened at 3:20 p.m. and was most likely caused by a gas leak and something that ignited it.

The Department of Buildings says the gas has been shut off for three buildings on the block, but the home of the explosion is structurally sound as are the neighboring homes.

A full vacate order has also been issued for 1522 Paulding Ave.

The DOB says its plumbing inspectors found that gas piping, fittings, valves, water lines, and waste lines for the use of laundry washing machines, gas-powered dryers, and a hot water heater for the laundry, had all been illegally installed in the ground-floor garage area. 

The DOB says the work was performed without proper permits or approvals.

The DOB says violations have been issued to the property and the owner for the illegal unpermitted gas work. 

A neighbor told News 12 the area where the explosion took place used to be a laundry room. Families who live next door said they are dealing with no heat following the explosion.

In the middle of a winter storm, neighbors tell News 12 a mother had to throw her child out of her apartment window to save the child's life. She added that the blast felt like an earthquake and was completely shaken up and can't believe the family survived. Still, neighbors said they are thankful that no one was killed in the explosion.

The American Red Cross says it has helped two families comprised of nine people who were displaced by the explosion.

The cause of the explosion has not yet been determined.

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