ELIZABETH, N.J. (CBSNewYork/AP) —  One person is dead and several others are injured following an apparent gas explosion at a house in Elizabeth on Wednesday morning, authorities said.

As CBS2’s Christine Sloan reported, cameras captured the 8 a.m. blast that left the duplex home on Magnolia Avenue severely damaged. The blast pancaked the second floor onto the first level, and the roof was seen blasting up as a fireball erupted.

A man was killed on the second floor, and firefighters were seen treating numerous victims on stretchers outside after 16 people were pulled from the wreckage alive. Two people, including an 11-year-old girl, were in critical condition, officials said.

One person initially unaccounted for in the explosion was later located, and turned out not home at the time of the blast.

Neighbors were left in shock by the blast.

“I come outside, and the building fell down,” said Mike Williams. “Like a tornado hit it. It just fell down.”

Kayon Pryce, who lives next door, said the force of the blast knocked him out of bed.

“I was in bed on a phone call,” Pryce told 1010 WINS’ Juliet Papa. “My bed actually got tossed up. The phone flew out of my hand. The windows came shattering in.” He said a television set also hit him in the face.

David Gonzalez said he felt the blast in his home four blocks away.

“I checked the windows because my windows cracked,” he told WCBS 880’s Levon Putney.

But for those in closer proximity, it was far worse. Wayne Sheppard, who lives next door, told CBS2’s Sloan that his house was completely demolished.

“I could hear my wife screaming; my son crying,” Sheppard said.

“I came from the back of the house, and it’s bad,” he said. “We probably lost everything except each other.”

Sheppard told his wife to run with their baby.

“I told them to get out of the house,” he said. “I grabbed the clothes I had by the door. My cellphone was by the door, and I got out.”

The force of the explosion was so strong that Sheppard’s windows were blown out.

“She had just taken him out of his bedroom,” Sheppard said. “His bedroom window is directly across from the house that exploded.”

Two other homes also sustained damage, CBS2’s Ilana Gold reported. Seven buildings were evacuated, authorities said.

PHOTOS: Elizabeth House Explosion

A Twitter user who lives in the neighborhood posted several photos and video from the scene. In one video, neighbors are seen running from the house next door shortly after the explosion.

The cause of the explosion remained under investigation late Tuesday.

“Whether it is a natural gas episode or there is an illegal gas connection, or there’s propane, has yet to be determined,” said Elizabeth Mayor Christian Bollwage.

Bollwage said it does not appear anyone was injured in the surrounding houses.

Many victims survived because they were upstairs sleeping in on the Veterans Day holiday. They rode the fall down.

Firefighters said luck was on their side, given that there was no big fire with the explosion.

“We had a flash fire with the initial explosion. We’re very fortunate that we didn’t get a major fire afterwards,” said Elizabeth fire Chief Tom McNamara. “It would have been a whole different ball game.”

Some neighbors said they smelled gas the day before. Officials said there was no record of it being reported.

“Anybody watching or listening to this — if you smell gas, call the appropriate people,” Sheppard said. “It may be nothing, but it’s better to call and find out it’s nothing than to go through something like this.”

It’s likely all three affected homes will have to be torn down, Papa reported.

A total of 30 people were displaced by the explosion. The Red Cross is helping seven families at the Second Macedonia Baptist Church at 1251 Fairmont Ave.

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