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EXCLUSIVE: Deranged doctor’s motive — and why he timed the shooting of Bronx hospital for this week

THE BRONX — If he couldn't become a full-fledged M.D. — neither would his arch enemy.

Dr. Henry Bello, the former medical resident at Bronx Lebanon Hospital Center who shot six people before mortally wounding a female doctor and himself, wanted to make sure that a fellow resident didn't become a licensed physician this week.

There's supposed to be a "transition" ceremony this week for the residents who have trained at Bronx Lebanon since 2014. Bello used to be part of that group, until he was forced to resign in 2015, because of sexual harassment allegations.

Bello blamed another resident, a male, for the complaints that built up about his behavior. A nurse at the hospital had reported Bello was sexually harassing her.

He already had arrests in his past for sexually inappropriate behavior, but they didn't stop him from becoming a resident at Bronx Lebanon in 2014. He had received a New York State permit to practice medicine, under the supervision of licensed, hospital physicians.

When Bello turned up on the 16th floor Friday, he asked for the male resident that he harbored such resentment for. That resident was supposed to "transition" this week in the hospital ceremony and officially become a doctor who could practice on his own.

But the resident was off.

So, Dr. Bello used his rifle to shoot up the nurses' station on the 16th floor.

He hit three medical students, a doctor and a patient there, before he ran to the 17th floor, where he killed Dr. Tracy Sin Yee Tam of Queens who, tragically, was filling in for another doctor Friday.

Dr. Tam normally worked in the hospital clinic. Bello shot and wounded another doctor who was with Tam, before turning the rifle on himself and committing suicide.

A law enforcement source told PIX11 Saturday evening, "His dreams of a medical career were over. He blamed everybody but himself for this."

The male resident who was being targeted for execution was interviewed by cops Friday night.

Detectives are investigating whether Henry Bello was a dental student, at one point.

There's information he may have "failed out" of a school in the Carribean, but this needed to be further explored.

The Nigerian-born medical professional, who was 45, had been in the United States for quite some time, but it wasn't clear if he arrived here initially in 1994 or later, in 2001.

PIX11 learned from the law enforcement source that Henry Bello "came from money" — a wealthy family in Nigeria.

But money couldn't solve Bello's problems, which included various arrests for burglary, turnstile jumping, and sexually inappropriate behavior toward women.

In 2004, a woman in Manhattan claimed he'd grabbed her by the crotch and lifted her up and said, "You're coming with me."

Bello cut a deal with the Manhattan District Attorney's office, pleading guilty to unlawful imprisonment and receiving a sentence of community service.

In 2009, he was arrested for unlawful surveillance, after two women complained he was using a mirror to look up their skirts.

It was a sexual harassment complaint that pushed Dr. Bello out of his residency at Bronx Lebanon Medical Center in 2015.

He wrote an e-mail to the Daily News, complaining that specific co-workers ruined his career, two hours before he started firing his rifle on the 16th floor of Bronx Lebanon. He had carried the weapon into the hospital tucked inside his white lab coat.