@nbcla: Brian Thompson, the CEO of UnitedHealth Group's insurance unit, was fatally shot in midtown Manhattan Wednesday morning, a person familiar with the matter told CNBC. UnitedHealth Group canceled its investor day after reports emerged of the shooting. Thompson led UnitedHealthcare, the largest private health insurer in the U.S. Police are investigating the shooting as a targeted attack, according to a person familiar with the matter. #nbcla #UnitedHealthcare #NewYork #Manhattan