Officer Encountered Trump Rally Gunman on Roof Moments Before Shooting

Officer encountered Trump rally gunman moments before shooting. Sources are reporting that a local law enforcement officer encountered the gunman who opened fire at Donald Trump's Pennsylvania rally just moments before he fired at the former president. The official says rallygoers alerted officers to the man who had climbed onto the roof, but when an officer climbed up, he pointed his rifle at the officer. Correspondent Evan Lambert joins "NewsNation Now" with the latest as details continue to emerge from the investigation into the assassination attempt.

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