Almost 24 hours since four East Village buildings were ravaged by a gas explosion, city officials cannot confirm any fatalities from the 7-alarm fire even as the number of injured grew.

Mayor Bill de Blasio told reporters Friday that there were 22 people injured by the blast. Eighteen did not have life-threatening injuries while four remain in critical condition.

De Blasio also confirmed two people were still unaccounted one day later as firefighters continue to douse the fire that collapsed three of the four buildings on Second Avenue.

Both Nicholas Figueroa and a restaurant busboy identified as Moises Lucon were unaccounted for, police said.

"You rarely see a scene of such devastation in the middle of a city like this," de Blasio said before he praised first responders, who arrived at the scene within 3 minutes on Thursday.

Six of the about 250 firefighters responding to the blast were injured.

Investigators still can't access the alleged source of the explosion at 121 Second Ave., where officials said contract workers were installing an expansion to the gas main that Con Edison said had been shut off earlier.

Before the explosion, Con Edison sent inspectors to the basement and found the work on main to be unacceptable.

"There is a possibility that the gas main was inappropriately accessed…by people in the building, but we don't know enough yet," de Blasio said, adding that there was no gas smell during the inspection.

NYPD Chief of Detectives Robert Boyce said the building owner called the contractor after Con Edison left the basement to complain about a gas smell. The contractor and the owner's son then went down to the basement. It exploded when they opened the door, Boyce said.

The city said there were no city permits on the site specific to that day.

Firefighters continued to put out fires at the East Village corner Friday afternoon and could stay there as long as a week as rubble is cleared from the site and can cause flare ups.