• The  murderer from Oklahoma targeted the doctor who did his back surgery.
• The attacker opened fire with a handgun and an AR-15-style weapon.
• After a five-minute shooting spree, the shooter killed himself.

A gunman who killed four people at an Oklahoma hospital targeted the doctor who did his back surgery.

Michael Lewis, the gunman who opened fire on the St Francis Hospital campus in Tulsa, is identified.

The gunman blamed his agony on the doctor who performed his back surgery, Dr. Preston Phillips. One of those slain in the incident was Dr. Phillips.

Read more: Four killed in St Francis Hospital, Oklahoma in gun rampage

The attacker opened fire with a handgun and an AR-15-style weapon. Lewis had bought one gun an hour prior to the shooting, and the other three days prior. Both are thought to have been purchased legally, according to the police chief.

After a five-minute shooting spree, he killed himself. He parked on the second floor and entered Dr. Phillips’ office on that floor. According to authorities, he then shot “indiscriminately” at anyone who got in his way.

Lewis had a note on him, police tells. He “made it apparent that he walked in with the purpose to kill Dr. Phillips and anyone who went in his way.”

Dr. Stephanie Husen, an orthopaedic surgeon, was the other doctor killed. While, the other two victims were a receptionist named Amanda Green and a patient named William Love.

Mr. Love was shot holding a door closed to let someone else to flee out of another door. Whereas, another victim was holding a door open to allow someone else to run away.

Lewis had gone to an appointment the day before the shooting, and Dr. Phillips had been working to help him. He had discomfort following his surgery on May 19th.

His wife called the cops after he contacted her. It was either before or during the shooting, informing her of the incident.

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There was also a bomb threat at his home, but the details are still being worked out.

“Dr. Phillips was a consummate gentleman, and he is a guy we should all try to emulate,” a representative for St Francis said.

It’s mind-boggling that someone would go after Dr. Phillips. He’s one of those people whose clinic isn’t usually on time, because he’ll spend every minute with patients who need it.

“It’s not just shocking, but it’s also the ultimate loss for St Francis,” he added.

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