Four firefighters were injured after flames broke out on State Street in Perth Amboy.
Officials say the blast blew the wall out by the back staircase - the staircase that residents used to escape.
Eric Hernandez was jolted out of bed around 4 a.m. He grabbed his kids and ran.
"Yeah - explosion and come outside everybody," he said.
Perth Amboy Fire Department Chief Edward Mullen said that crews arrived to find glass all over the street, as well as a heavy fire in the basement.
Hours after explosion in basement, building demolished; concerns will collapse, FFs couldn’t put out hot spots. 12 residents on 2nd floor of Perth Amboy State St. building escaped unharmed 4am. 4 firefighters minor injuries. 18 families in 3 adjacent buildings also evacuated. pic.twitter.com/20uayzZkrO— CeFaan Kim (@CeFaanKim) November 18, 2018
Officials say that whatever it was that blew up was in the basement, below the ground floor restaurant.
The twelve residents on the second floor of the building escaped unharmed.
Four firefighters were injured. It took more than a hundred firefighters more than two hours to get flames under control.
Residents in three adjacent buildings also had to be evacuated - 18 families in all.
"The one wall facing Dekalb Street was already bowing out, so in order to keep the public safe, we wanted to make sure the building was down," added Chief Mullen.
The cause of the fire remains under investigation.
The 18 displaced families could possibly return home Sunday night after a gas check.
The injured firefighters were all treated and released from the hospital.
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