She was not supposed to be working when Bello went on his rampage, just two hours after he emailed a newspaper blaming the hospital for ruining his career and ranting about his former colleagues.
A doctor who killed another physician and wounded six other people at the Bronx-Lebanon Hospital Center had sent an email to the New York Daily News two hours earlier.
In the email, Henry Bello said the hospital blocked his path to obtaining a license to practice medicine in New York state.
He also said he had been accused of threatening a colleague, one in a series of what he called “bogus complaints.”
Bello, 45, wearing a white lab coat, stalked two floors of the hospital, opening fire with an AR-15 rifle on his former colleagues before trying to set himself on fire and then shooting himself to death.
He reportedly went first to the 16th floor where he saw a doctor and yelled, “Why didn’t you help me when I was getting in trouble?”
He fired, missing the doctor but hitting others standing at a nurses’ station.
Then he took out a container of flammable liquid, poured it on the floor and ignited it.
After that, he climbed the stairs to the 17th floor and shot two physicians, killing one and wounding the other, before he fatally shot himself in the chest.
Bello fired eight times and had 10 bullets in his pocket.
Dr Tracy Sin-Yee Tan, the female doctor Bello killed was not supposed to be at work that day but was covering a shift as a favour to another doctor.
As Tam stood with another physician on the 17th floor of the hospital, Bello shot them both, killing her.
Like Bello, 32-year-old Tam was a family medicine doctor. She graduated from the Touro College of Osteopathic Medicine in 2013.
Tam was not married.
“Her career was her boyfriend,” said neighbour Pat Vicencio, 55. “I lost a very nice friend. I didn’t think she was the one.”
“She never said no,” said Judy Beckles-Ross, 46, a distraught friend. “She’s done it before. I invited her to a party once, and she had covered for someone.”
“She had a good heart,” said Beckles-Ross. “Anybody that needed help, she would help them.”
A hospital spokesman said Tam was well-liked.
The doctor who had taken Friday off was reportedly “totally grief-stricken” and spending time with Tam’s family.
Ahmed Rezk, a family physician who went to medical school with Tam and worked closely with her, started a GoFundMe page to raise funds for Tam’s funeral expenses and her family, believed to consist of her mother and sister. Within a day, nearly US$20,000 of the US$25,000 goal has been raised.
Tam, who joined the hospital a year after Bello’s departure, was not Bello’s intended target.
Bello was reportedly gunning for Dr Kamran Ahmed, 48.
Ahmed said he had no idea why the deranged shooter wanted him dead.
“The strange thing is he was nice with me,” said Ahmed. “I’m shocked. He had a problem with almost everybody.”
Ahmed said he knew and respected Tam.
“Everybody loves her,” he said. “She loves to teach. She’s excellent. I feel so sorry about her, she was there to cover for one of the attendings.”
Ahmed, a family medicine doctor, declined to comment on a neighbour’s claim that Bello had recently sent him threatening emails. But he acknowledged speaking with New York Police Department (NYPD) investigators.
The fortunate doctor had the day off when Bello went hunting for him.
The injured largely suffered gunshot wounds to the head, chest and abdomen. The victims comprised a patient, two medical students and three doctors, one of whom is still in critical condition.
Police said Bello had purchased the assault rifle used in the rampage less than two weeks earlier from a gun store. The box for the gun was found in his apartment.
He had concealed the weapon under his white lab coat as he entered the hospital.
Bello’s former co-workers described a man who was aggressive, loud and threatening.
“All the time he was a problem,” said Dr David Lazala, who trained Bello.
When Bello was forced out in 2015, he sent Lazala an email blaming him for the dismissal.
Dr Maureen Kwankam told the Daily News that “he promised to come back and kill us then”.
Citing unnamed sources, media reports said Bello had resigned from the hospital rather than face termination over accusations of sexual harassment.
He had worked in the hospital for about six months until his departure in February 2015.
According to New York state education department records, Bello graduated from Ross University and had a permit to practice as an international medical graduate that was issued on Jul 1, 2014, and expired last year on the same day.
He also worked as a pharmacy technician at Metropolitan Hospital in Manhattan because he was having a hard time getting licensed as a physician, but quit the job in 2012 and filed for unemployment, according to the lawyer who represented him on appeal in 2014.
He lost his case.
According to The Guardian newspaper, one former colleague at Metropolitan said he would frequently argue with nurses and bristled at being told what to do, but his attorney in the unemployment action said that was not the man he knew.
“I’m absolutely shocked,” attorney David Wim said. “He was such a nice gentleman. He was very humble, very polite, very respectful.”
Bello was unmarried.
In 2004, he pleaded guilty to unlawful imprisonment after a woman told police Bello grabbed her.
He was arrested again in 2009 on a charge of unlawful surveillance after two women reported he was trying to look up their skirts with a mirror.