Updated on: April 28, 2026 / 7:06 PM EDT / CBS News Add CBS News on Google The alleged gunman was running at full speed as he raced past the magnetometers on the second floor of the Hilton hotel in Washington, D.C. He discharged his shotgun, likely hitting the cellphone tucked inside the pocket of the bulletproof vest worn by the officer who fired five shots at him, according to two sources familiar with the investigation of the incident Saturday night at the White House Correspondent's Dinner .    Officials investigating the incident said they estimated 31-year-old Cole Tomas Allen was running at about 9 miles per hour when he sprinted through and discharged the shotgun he had with him. Officials are still conducting ballistics testing to confirm whether it was the shot he fired that hit the officer wearing the bulletproof vest in the chest, sources said.…