NEW YORK, March 27 (UPI) -- Authorities say two people are still missing in the aftermath of a fiery explosion in New York City's East Village -- a blast that was reportedly preceded by a visit from city utility inspectors.
Earlier Friday, investigators said they were still searching for up to eight people. The explosion, possibly caused by a gas leak, injured nearly two dozen people and leveled three buildings in Lower Manhattan. Firefighters were among the injured, officials said.
Of the missing people, Nicholas Figueroa, 23, and another person are thought to have been near or inside the buildings just before the explosion. Firefighters continued Friday morning to extinguish smoldering areas of fire and sift through the wreckage of three collapsed buildings in New York City's East Village, including the Sushi Park restaurant.
Family members said Figueroa was at lunch with a co-worker at Sushi Park and paid the bill shortly before the explosion. He has not been heard from since the explosion.
Four people remain in critical condition, including two with burns to their airways and one who was rendered unconscious during the seven-alarm fire that brought some 200 firefighters to the scene.
Mayor Bill de Blasio said the explosion, which took place at about 3:15 p.m. Thursday, appears to be tied to work on the gas and plumbing lines.
Multiple news outlets reported late Friday that the explosion may have resulted from an inappropriate tapping into the natural gas line. In other words, the pipe may have been configured in such a way to allow a resident or business to tap into the line's gas without the utility company's knowledge -- and a subsequent leak may have facilitated the blast.
Newsday reported Friday that only the sushi restaurant was served by the gas line. Also, incidentally, workers from Consolidated Edison, a New York utility company, had apparently been making efforts to add new gas and plumbing systems to the building -- which put inspectors at the explosion site immediately preceding the blast.
The Con Ed workers left the site at 2:45 p.m., approximately a half hour before the explosion occurred. Authorities have not yet commented or speculated whether the utility's presence may have had any influence on the explosion.
Hyeonil Kim, 59, the owner of the destroyed restaurant said Friday that he has long wondered how the tenants above him in the five-story residential building were getting gas for hot water and cooking when his business had sole authority to use the utility line, the New York Times reported.
Kim reportedly told his landlord that he detected the smell of gas about 15 minutes before the explosion.
"The strong assumption is a gas explosion; we are waiting for details," de Blasio told reporters. "There is some X factor we don't know yet we have to find."