
A doctor who shot seven people, killing one woman, before turning the gun on himself at a New York hospital had been forced to resign over sexual harassment accusations.

The gunman, Dr Henry Bello, shot himself after trying to set himself on fire at the Bronx Lebanon Hospital at around 2.45pm on Friday.

He staggered, bleeding, into a hallway where he collapsed and died with the rifle at his side, police have said.

A former colleague described the 45-year-old as a problematic employee, and said he was 'aggressive, talking loudly, threatening people.' In 2015, he was allowed to resign from the hospital after being accused of sexual harassment.

The attack on Friday left several doctors fighting for their lives, and witnesses described a chaotic scene as gunfire erupted, spreading terror throughout the medical facility. Employees locked themselves inside rooms and patients feared for their lives.

'I thought I was going to die,' said Renaldo Del Villar, a patient who was in the third-floor emergency room getting treatment for a lower back injury.

Bello was described on the hospital's website as a family medicine physician, and police said he used an AR-15 assault rifle in the attack on the 16th and 17th floors. Police Commissioner James O'Neill confirmed he died of a self-inflicted gunshot wound.

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First image: Dr Henry Bello, 45, has been named as the deceased gunman who carried out a deadly attack at his former place of work, the Bronx Lebanon Hospital, Friday afternoon

Six people were shot at Bronx Lebanon Hospital after a former employee dressed as a physician opened fire with a semi-automatic rifle. First responders are seen with stretchers outside the entrance

In 2015, Bello was allowed to resign from the hospital amid sexual harassment allegations, according to two law enforcement officials. They did not know the details of the allegations, and agreed to speak on condition of anonymity because the investigation is still unfolding.

The gunman (pictured) shot himself after trying to set himself on fire at the Bronx Lebanon Hospital at around 2.45pm on Friday. He staggered, bleeding, into a hallway where he collapsed and died with the rifle at his side, police have said

However, Dr Maureen Kwankam, 50, told the New York Daily News he was fired from the hospital 'because he was kind of crazy.'

'He promised to come back and kill us then,' she said.

Ultimately, one female doctor was killed and six others wounded - five seriously, according to Police Commissioner James O'Neill. The patients were treated in the emergency room at Bronx Lebanon.

He also tried to set fire to the nurses station on the 16th floor, but the hospital's sprinkler system put it out before the blaze could grow.

'This was a horrible situation unfolding in a place that people associated with care and comfort, a situation that came out of nowhere,' New York City mayor Bill de Blasio said.

He also said terrorism did not play a role.

According to New York State Education Department records, Bello had a limited permit to practice as an international medical graduate to gain experience in order to be licensed. The permit was issued on July 1, 2014, and expired last year on the same day.

Bello 'was very aggressive, talking loudly, threatening people. All the time he was a problem,' said Dr. David Lazala, a family medicine doctor who said he trained Bello at Bronx Lebanon.

He said Bello, who worked at night as a doctor, sent him a threatening email after Bello was fired.

Police said Bello used an AR-15 assault rifle, which is pictured at the hospital on Friday, to carry out his attacks on the 16th and 17th floors of the hospital

NYC Mayor Bill de Blasio called the incident a 'horrible situation' and said it was not related to terrorism but instead just a workplace incident

A woman is escorted by officers in plainclothes near the Bronx Lebanon Hospital in New York Friday after fleeing the gunman

A woman is escorted by officers near the Bronx Lebanon Hospital in New York after a gunman opened fire there

The incident unfolded at around 2.45pm at the medical center on Grand Concourse in the Morris Heights section of The Bronx

In unrelated cases, the doctor had been arrested in 2004 on a charge of sexual abuse, according to a police report, after a 23-year-old woman told police Bello grabbed her, lifted her up and carried her off, saying, 'You're coming with me.'

He was arrested again in 2009 on a charge of unlawful surveillance, after two different women reported he was trying to look up their skirts with a mirror.

Employees and their loved ones described the horrifying moments immediately after the shooting as they scrambled for information.

Garry Trimble said his fiancee, hospital employee Denise Brown, called him from inside the hospital to tell him about the gunman.

'She woke me up and told me there was a situation, somebody's out there shooting people,' Trimble said as he waited for Brown to leave the hospital. 'I could hear in her voice she was shaking and about to cry.'

Heavily armed police patrol the scene outside the hospital after the gunman opened fire on Friday afternoon

Police sources say the gunman was hiding the high-powered weapon under his lab coat before the attack on the 16th floor of the hospital

Hospital employees barricaded themselves in hospital rooms by stacking furniture up against the doors during the lockdown

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.

Witness Dione Morales, who has been a patient at the hospital for 17 years, told CBS New York the shooter had threatened to kill people back when he was fired.

'He was let go because I guess they figured he was unstable. He said he was going to do this,' she said. 'He said he was going to kill people, two years ago when he was let go - two years... and now look what happened.'

Incident began unfolding at around 2.45pm at the medical center on Grand Concourse. Police say the gunman had an AK-15 rifle

Officers carrying assault-style rifles are posted outside the Bronx Lebanon Hospital where a former employee stages a deadly rampage

Dr Bello is believed to have lived in this New York City apartment building. He was forced to resign from his position at the hospital in 2015 after sexual assault allegations became public

Police cars are seen parked outside the hospital on Grand Concourse during the active shooter situation

Bronx-Lebanon Hospital Center describes itself as the largest voluntary, not-for-profit health care system in the south and central Bronx.

The 120-year-old hospital claims nearly 1,000 beds spread across multiple units. Its emergency room is among the busiest in New York City.

The hospital 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.

Fire Department rescue workers head towards the scene after the inside the Bronx-Lebanon Hospital in New York City