A highly-acclaimed trauma surgeon, who treated legendary U2 lead vocalist Bono when he had a terrible bicycle accident, was found dead in his New York home Sunday.

The body of Dean Lorich was discovered by his 11-year-old daughter, lying on the bathroom floor, with his face turned up toward the ceiling at 1 p.m. EST. Seeing a knife sticking out of her father’s chest, Lorich’s daughter ran downstairs to fetch the doorman, who then called emergency services.

Lorich, 54, was the associate director of the Orthopedic Trauma Service at Hospital for Special Surgery and the chief of the Orthopedic Trauma Service at New York-Presbyterian Hospital, according to New York Post.

He was the one who successfully performed several surgeries on Bono after he fractured his eye socket, shoulder, and elbow from a bad fall from his bike in 2014. Bono was admitted to New York-Presbyterian/Weill Cornell Medical Center after the rock star lost control of his bike, making a hard swerve in order to avoid colliding with another cyclist.

Investigators are looking into the possibility of Lorich taking his own life since there are no signs of forced entry in his apartment. Authorities have not found a suicide note so far.

Lorich lived in an Upper East Side apartment on Park Avenue with his wife and three daughters. At the time, Lorich’s wife was not present inside the house. She was out playing tennis.

Although the police did not go into the details, they did reveal that Lorich was going through some kind of “personal stress” in recent times.

According to a report by the New York Daily News, an unnamed woman, believed to be one of Lorich’s female colleagues, showed up at the apartment after the police arrived at the scene. After she spoke to the doorman, she knelt on the ground and started to pray.

“This is horrible, this is horrible. I don’t believe this,” the woman was heard saying. She declined to give her name.

Although Lorich’s came to the media spotlight after helping Bono recover from his injuries, there were others that the orthopedic had aided during his life, a number of whom belonged to various law enforcement agencies.

In 2005, he tended to NYPD Officer Tarrell Lee and firefighter Matt Long, who had been run over by an SUV and a bus respectively. Long, who went on to become friends with Lorich, said that he was in shock after hearing about Lorich’s death.

“He was a good doctor, and a good man,” Long said. “He saved and helped so many people. He gave me back my life, and my family and I are all devastated. He came to my wedding. He was part of my life ... This guy did so much for me. He sacrificed his whole life to help other people, and I happen to be one of them.”

Lorich also had a charitable nature. He was among the many physicians who volunteered for aiding the victims affected by the Haiti earthquake in 2010.

“It’s devastating news. Dean was a friend and a tremendous doctor,” said Dr. Soumi Eachempati, who accompanied Lorich during the natural disaster. “The medical community will have an extremely large void without him.”