Two hours before opening fire at a Bronx, New York, hospital, the doctor suspected of going on Friday afternoon's deadly rampage sent an email to a local newspaper claiming his former employer had destroyed his career.
"This hospital terminated my road to a licensure to practice medicine," Dr. Henry Bello wrote in an email sent at 12:46 p.m to the New York Daily News, which published it in Saturday's edition. "First I was told it was because I always kept to myself. Then it was because of an altercation with a nurse."
Bello, 45, wore a white doctor's coat and wielded an assault rifle when he stormed the Bronx-Lebanon Hospital at around 2:55 p.m., killing one person and injuring six others, the NYPD said.
He then took his own life with a gun on the 17th floor of the hospital, police said, adding that he also attempted to light himself on fire before his death.
Police on Saturday identified the lone victim as Dr. Tracy Sin-Yee, 32. Although she typically works in the clinic, she had been asked to cover the shift of a colleague on Friday, hospital officials told NBC New York. She had worked at the hospital for about a year.
In the email, Bello told the Daily News that he sent an email to a colleague congratulating her for his firing "after she sent out an email to everybody telling them to file complaints against me so I can be terminated for being rude to her."
"I only said in the email, it remains to be seen if my life is meaningless or disposable," the disgruntled doctor added.
Bello was hired at the hospital in 2014, but was forced to resign six months later, NBC New York reported. Police said Bello had a long criminal history that included sex abuse and unlawful surveillance.
Bello appeared to use his old credentials to gain access inside the hospital.
According to a senior NYPD official, Bello asked for a specific doctor. When he found out that person was unavailable, he began unloading his weapon.
"All these bogus complaints are the work of Dr. [Name Redacted], who felt the chairman should never had hired me and he made sure I never completed my program," Bello wrote in the email to the Daily News.
Bello then alleged that the doctor blocked him from gaining a medical permit.
The email does not include any threats of violence.
Bronx-Lebanon Hospital did not immediately respond to a request for comment Saturday about the letter or Bello's employment status.