the M gunman who stalked and killed the CEO of United Healthcare used ammunition with the words deny defend and oppose on it according to a law enforcement official the words on the ammunition may have been a reference to strategies insurance companies used to try to avoid paying claims the CEO Brian Thompson died in a dawn ambush in Manhattan as he walked at the company’s annual investor conference at a Hilton hotel investigators recovered several 9mm shell casings from outside the hotel and a cell phone from the alleyway through which the shooter fled investigators believe that the shooter had had at least some prior firearms training and the weapon used was equipped with a silencer the shooter approached Thompson from behind and fired several shots barely pausing to clear a brief gun Jam while Thompson tumbled to the pavement the shooter is still at Large