Calling the incident a “brazen targeted attack,” police said the suspect was waiting for Thompson before shooting him outside of a hotel in Midtown Manhatten. But while authorities stressed that the killing was “premeditated” and planned, the motive for the shooting is still unknown.

Brian Thompson, the CEO of United Healthcare, was killed by a masked gunman outside a hotel in City where he was expected to speak to a ballroom full of colleagues, officials said.

The shooting of the CEO outside of a New York conference center will disrupt the country's largest private healthcare provider.

NEW YORK -- Brian Thompson, the CEO of United Healthcare, was shot and killed by a masked man near a Midtown Manhattan hotel early Wednesday, according to police sources. The shooting appears to be targeted but police do not know why, sources said. Thompson was not staying at the Hilton outside of which he was shot, sources said.

Watch live coverage as the New York Police Department and other authorities hold a briefing on the fatal shooting of the United Healthcare CEO in New York City.

UnitedHealthcare CEO Brian Thompson was fatally shot Wednesday morning outside of a Hilton hotel in New York City, according to multiple reports. Thompson, the 50-year-old leader of the health care giant’s insurance unit,

Police have not identified the suspect, who remains on the loose and was last seen riding an electric Citibike in Central Park, officials said.