Crews are still sifting through the rubble and searching for two men who remain missing after Thursday's explosion in the East Village.
Sources say 23-year-old Nicholas Figueroa was on a date, paying for a meal at the sushi restaurant in the building where the explosion happened.
His date is in the hospital.
Sources say 26-year-old Mosies Lucón was the worker at the cash register.
Twenty-two people were injured, including six firefighters. Four people were critically hurt. One person remains hospitalized in good condition.
Investigators believe the explosion originated in the basement. The focus of the investigation is a new gas system private contractors were installing.
Sources say it was discovered last year that someone tampered with the meter, possibly in an attempt to avoid paying for gas.
Sources say investigators want to know whether workers were attempting something similar Thursday.
"It’s going to be slow and arduous to dig out and search through the rubble. They’re searching very carefully. It will be a week’s operation day and night for us to work through it and we're still looking for two missing persons. And that's about it. It's a tough job," said Fire Commissioner Daniel Nigro.
Health officials say the air quality is back to a healthy level and has been for days.