Gunman in Trump rally attack flew drone over rally site in advance of event, official says

Read MoreThe gunman in the attempted assassination of former President Donald Trump is believed to have flown a drone around the Pennsylvania rally site ahead of time in an apparent attempt to scope out the site before the eventThe gunman in the attempted assassination of former President Donald Trump is believed to have flown a drone around the Pennsylvania rally site ahead of time in an apparent attempt to scope out the site before the event