A doctor who used to work at a Bronx hospital returned with a rifle hidden under his white lab coat and opened fire Friday, killing one person and wounding six others before apparently taking his own life, authorities said.

The gunfire broke out at 2:50 p.m. inside the Bronx Lebanon Hospital, drawing police cars and firetrucks to the scene and sending officers onto the roof with their guns drawn as people inside the building were told to hide, reports the Associated Press .

Officers went floor by floor looking for the gunman and reported just before 4 p.m. that the shooter was dead inside the building. A law enforcement official told The Associated Press that the gunman apparently killed himself.

He was identified by law enforcement officials as Dr. Henry Bello, a family medicine physician at the hospital. It was not immediately clear why he was no longer working at the hospital.