New York City firefighters spent the overnight hours digging through rubble in search of missing people after a deadly explosion in East Harlem near the intersection of 116th street and Park Avenue.

Unfortunately, fears turned into harsh realities as bodies were recovered. More than a half dozen deaths have been confirmed while a number of people still remain missing. New York City mayor Bill de Blasio has remained hopeful that there could be some people still alive after the explosion that rattled several Manhattan blocks.

"We are continuing rescue operations hoping to find others still alive," de Blasio said during a press conference. "Everyone involved in the rescue effort has given their all."

Mayor de Blasio also spoke directly about the first responders and the work they did in the aftermath of the explosion.

"I can only imagine knowing that at any moment you might find a body, how difficult that is," de Blasio said as he was being briefed on Thursday morning at City Hall. "I admire the work you guys do. I really do. It's not easy."

The explosion, which occurred shortly after 9 a.m. on Wednesday, was so sudden that real hints and suspicion only arose 20 minutes before everything was suddenly engulfed in flames. While some people suspected a smell of gas the night before, officials were not notified until the following day, according to the New York Times.

Although Con Edison officials were on their way to the explosion only two minutes after the phone call that reported a gas issue, it was too late. The explosion that rocked Manhattan happened so fast that the officials arrived only after it was too late.

There is still more investigating to be done and more searching to do, and there is likely to be more information released in the coming hours and days.