At least four people have been hurt by the shooter, who opened fire at around 2.45pm local time (7.45pm BST).
The body of a woman who was shot was found near the body of the shooting suspect, the officials tell CNN.
The NYPD is responding to a shooting at Bronx-Lebanon Hospital this afternoon.
NY police urged the public to avoid the area around the hospital at 1650 Grand Concourse.
Multiple people were shot, though the extent of their injuries was not immediately known, according to police.
The New York Police Department told members of the public to avoid the area around the hospital.
The New York City mayor tweeted saying he was aware of the situation.
This is a breaking story, more to follow.
- NYPD NEWS (@NYPDnews) June 30, 2017One shooter is deceased at the hospital.
"Active shooting in Bronx Leb". Shots were reported at around 3 p.m.
Police identified the gunman as Henry Bello, a former doctor at the hospital.
Social media photos from inside the hospital show employees barricading themselves inside, waiting for the police to locate the gunman.