Authorities described a chaotic scene at Bronx Lebanon Hospital as gunfire erupted at around 2:50 p.m., spreading terror throughout the hospital as employees locked themselves inside rooms and patients feared for their lives.
"I thought I was going to die," said Renaldo Del Villar, a 55-year-old patient who was in the third-floor emergency room getting treatment for a lower back injury.
Law enforcement officials identified the shooter as Dr. Henry Bello, who was described on the hospital website as a family medicine physician. He resigned from the hospital in 2015 after some sort of dispute, according to one law enforcement official, who said Bello used an AR-15 in the attack.
The officials were not authorized to discuss the still-unfolding investigation and spoke on condition of anonymity.
PHOTOS: Images from the scene
Ultimately, one female doctor was killed and six others wounded, Mayor Bill de Blasio said.
"This was a horrible situation unfolding in a place that people associated with care and comfort, a situation that came out of nowhere," de Blasio said.
The FBI tweeted that they had found "no nexus to terrorism" so far.
Shortly after receiving a 911 call about an active shooter, police officers went floor by floor, their guns drawn, looking for the gunman. They learned just before 4 p.m. he was dead inside the building. De Blasio confirmed that the Bello killed himself, while Police commissioner James O'Neill said he tried to set himself on fire.
Employees and their loved ones described the horrifying moments as they scrambled for information.
Garry Trimble said his wife, hospital employee Denise Brown, called him from inside the hospital shortly after 3 p.m.
"She woke me up and told me there was a situation, somebody's out there shooting people," Trimble said as he waited for his wife to come out. "I could hear in her voice she was shaking and about to cry."
Gonzalo Carazo described the scary scene to WCBS-TV. "I saw one of the doctors and he had a gunshot wound to his hand," Carazo said.
"All I heard was a doctor saying, "Help, help!" Carazo locked himself in a room for about 15 minutes until police came and led him out of the hospital.
The 120-year-old hospital has nearly 1,000 beds and one of the busiest emergency rooms in New York City. It is about a mile and a half north of Yankee Stadium.
In 2011, two people were shot at Bronx Lebanon in what police said was a gang-related attack.
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