NEW YORK_The NYPD and FDNY are investigating an explosion that injured multiple people shortly after 8:30 p.m. in the Chelsea neighborhood of Manhattan.
The explosion was reported at 23rd Street and Sixth Avenue where fire crews and ambulances were descending onto the neighborhood.
Several residents reported hearing the explosion, but police did not have further details on the cause.
NYPD officials said several people were injured and transported to area hospitals.
The street has been closed off and there are unofficial reports that the bomb squad is on the scene with the FBI.
The NYPD Counterterrorism unit was responding to the scene, according to Twitter.
Mayor Bill de Blasio said on Twitter he was working with NYPD Commissioner James P. O'Neill and gathering facts about what caused the explosion.
De Blasio was staying in Gracie Mansion during the investigation as the situation remained fluid, aides said.
Earlier in the day a pipe bomb exploded in Seaside Park, New Jersey, near a Marine charity run. The device had been placed in a garbage can.
