Law enforcement officials have uncovered additional details in thefatal shootingof UnitedHealthcare CEO Brian Thompson.

Three live rounds and three fired shell casings were recovered from the scene by police.

The gunman wore a black mask and fled the scene on foot before riding off on a bike.

Crime Scene Unit police work at the scene where CEO of UnitedHealthcare Brian Thompson, 50, was shot as he entered the New York Hilton early on December 4, 2024 in New York. Brian Thompson, the chief executive of one of the United States’s largest health insurance companies, UnitedHealthcare, was shot and killed outside a New York Hilton hotel in an apparently targeted hit Wednesday, US media reported. (Photo by Bryan R. SMITH / AFP) (Photo by BRYAN R. SMITH/AFP via Getty Images)

Crime Scene Unit police work at the scene where UnitedHealthcare CEO Brian Thompson, 50, was shot as he entered the New York Hilton early on Dec. 4, 2024, in New York.BRYAN R. SMITH/AFP/Getty Images

The 50-year-old was pronounced dead after being transported to a nearby hospital.

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