Three are confirmed dead, with more than 20 people injured. And authorities say more than a dozen are missing after an explosion leveled two buildings in East Harlem, New York, this morning. 

New York City Mayor Bill de Blasio says a gas leak caused an explosion and fire that killed at least two people and leveled a pair of buildings today.  

The mayor said during a news conference fire crews are still working to put out the fire.  

De Blasio said "a number" of people are still missing.  

A fire is still burning in East Harlem, New York a gas pipe explosion appears to have caused two buildings to collapse at 116th Street and Park Avenue.

The two buildings are each five stories tall, in a largely residential area. Roads in the area have been closed off to traffic. 

About 20 are reported injured at this time. The identities of those killed have not been released.  Emergency crews and a bomb squad were on the scene. 

All service out of Grand Central Station were suspended, but they have since resumed. 

Con Edison officials say it could take days or weeks to determine the exact cause of this morning's deadly explosion in East Harlem.

Senior Vice President of Gas Operations for Con Ed, Ed Foppiano, says they will conduct a through investigation, and are treating it as if it were a gas leak. 

Con Edison officials say they were responding to a report from a Park Avenue neighbor of a gas smell just before the explosion occurred at 9:30 this morning.

Con Ed has shut down all electric and gas service along the Park Avenue block where the explosion occurred between East 116th and East 117th Streets, impacting five standing buildings that are evacuated.

Crews continue to work closely with the FDNY to make the area safe and determine the exact cause of this morning's explosion.

PHOTOS: Explosion in East Harlem