 Now with more CBS News, here's Debra Rodriguez. Mr. Trump made an unscheduled appearance at the convention with his fist held high, a white bandage on his ear. A reminder of Saturday night's assassination attempt at a rally in Pennsylvania. Video from the scene appears to show bystanders trying to warn police there was a gunman on the roof just before Thomas Matthew Crooks began to fire. CBS's Anna Schechter. Two officers who came for backup tried to get onto the roof.