ELIZABETH, N.J. (AP) — Officials have released the name of the man who died in a house explosion in New Jersey.

Police say 24-year-old Femi Brown lived on the second floor of the duplex that was leveled in Wednesday's blast in Elizabeth.

Two people, including an 11-year-old, remain in critical condition with severe burns.

City spokeswoman Kelly Vence said Thursday that officials have not yet determined what triggered the explosion. Mayor Chris Bollwage said Wednesday that gas was believed responsible. He described the blast as flattening the building "like a pancake."

In all, 14 people were taken to hospitals.

A neighbor says the explosion was so strong that it tossed him out of bed and knocked his phone out of his hand.