NEW YORK -- (WPIX) -- A portrait of an angry doctor seeking revenge on the medical professionals he believed turned their backs on him emerged Saturday as a New York hospital began to recover from his assault-weapon rampage that left one doctor dead, another critically injured and four staff members and a patient wounded.
Bello had warned his former colleagues two years ago that he would return someday to kill them after he was forced to resign amid sexual harassment allegations.
"This hospital terminated my road to a licensure to practice medicine," the email said. "First, I was told it was because I always kept to myself. Then it was because of an altercation with a nurse."
He also blamed a doctor for blocking his chances at practicing medicine.
A law enforcement official told The Associated Press that when Bello arrived at the hospital he asked for a specific doctor whom he blamed for his having to resign but the physician wasn't there at the time. The official spoke on anonymity because the person was not authorized to discuss an ongoing investigation.
It was not clear if Bello knew Dr. Tracy Sin-Yee Tam, 32, who was killed in the shooting on the 16th and 17th floors of the hospital and was, like him, a family medicine doctor. Hospital officials said Saturday that Tam normally worked in one of the hospital's satellite clinics and was covering a shift in the main hospital as a favor to someone else.
The victims largely suffered gunshot wounds to the head, chest and abdomen. Another physician remained in critical condition. One was a patient, two are medical students and the rest are physicians. All but one was in stable condition Saturday.
Hospital vice president Errol C. Schneer said his staff responded heroically.
"Many of our staff risked their own lives to save patients," Schneer told reporters at the hospital where the 16th and 17th floors remained closed, and staffers were still recovering from the rampage that sent people diving for cover and huddling in patients' rooms while the gunman was on the loose. Adding to the chaos, authorities said, was a fire alarm that went off when Bello attempted to set himself ablaze, the flames extinguished by sprinklers, shortly before he shot himself.
Detectives searched the Bronx home where Bello was most recently living and found the box where the gun came from. Investigators were checking serial numbers and trying to determine where it was purchased.
His 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 as a family medicine doctor. 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."