Brian Thompson, the CEO of UnitedHealth Group‘s insurance unit, was fatally shot outside the Hilton hotel in midtown Manhattan on Wednesday morning, in what is believed to be a targeted attack, a person familiar with the matter told CNBC.

UnitedHealth Group canceled its investor day set for Wednesday at the Hilton after reports of the shooting emerged. Thompson, 50, led UnitedHealthcare, the largest private health insurer in the U.S.

A spokesperson for the New York Police Department confirmed that a 50-year-old male was shot in front of 1335 Avenue of the Americas in New York, the address of the Hilton hotel, at 6:46 a.m. ET on Wednesday. But the spokesperson did not confirm the identity of the man.

A formal report from the department said emergency medical services responded and transported the man to the Mount Sinai West hospital in critical condition with a gunshot wound to the chest, and he was later pronounced deceased. No arrests have been made and an investigation is ongoing, the department added.

The suspect in the shooting is described as using a firearm with a silencer, the person familiar with the matter said. The suspect is also described as a white male wearing a black hoodie, black pants, black sneakers with a white trim and a gray backpack, the person added.

A hot dog vendor near the Hilton who was present at 6:30 a.m. ET said he did not hear any gunshots but noticed a sudden swarm of police. A Hilton doorman who began his shift at 7 a.m. ET said everything appeared to be “pretty normal” at the hotel. Both people asked not to be named.

The NYPD will provide an update on the shooting at a news conference at 11:30 a.m. ET.

Thompson is survived by his wife, Paulette Thompson, and their two children.

Thompson’s wife told NBC News that he had been receiving threats. She said the NYPD told her it was a planned attack.

“Yes, there had been some threats basically I don’t know, a lack of coverage? I don’t know details,” she told NBC News. “I just know that he said there were some people that had been threatening him.”

She told NBC News that Thompson did not alter any of his travel habits despite the threats.

“I can’t really give a thoughtful response right now,” Paulette Thompson told NBC News. “I just found this out and I’m trying to console my children. “

UnitedHealth Group is the biggest health-care conglomerate in the United States based on revenue and its roughly $563 billion market cap. UnitedHealthcare posted more than $281 billion in revenue last year, making up more than two-thirds of UnitedHealth Group’s annual revenue for 2023.

Shares of UnitedHealth Group rose more than 1% on Wednesday.

The company did not confirm the shooting but canceled the event when it acknowledged a “medical situation” with an employee.

“I’m afraid that we – some of you may know we’re dealing with very serious medical situation with one of our team members,” Chief Executive Officer Andrew Witty said during the investor day, according to a transcript. “And as a result, I’m afraid we’re going to have to bring to a close the event today, which I’m sure you’ll understand.”

Thompson had worked for United Health for just over 20 years, joining the company in April 2004 after spending nearly seven years at PwC, according to his LinkedIn page. He stepped in as CEO of UnitedHealthcare in April 2021 after serving as the top executive of the insurance unit’s government programs.

Thompson was a resident of Maple Grove, Minnesota, a suburb of Minneapolis, and graduated valedictorian from the University of Iowa.

Gov. Tim Walz of Minnesota called the killing “horrifying news and a terrible loss for the business and health care community” in a post Wednesday on X.

UnitedHealth Group did not immediately respond to a request for comment.

UnitedHealth Group is still grappling with the fallout from a ransomware attack in February targeting its company, Change Healthcare, which processes medical claims. The attack compromised the protected health information of at least 100 million people

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— CNBC’s Ester Bloom contributed to this report