four marines and one navy sailor gunned down in chattanooga by one lone terrorist. surprising information about the shooter. >> silver convertible mustang and he was just unloading some type of large rifle. >> then i heard boom, booming boom. >> i saw people from all the businesses around here, running toward the national guard facility. lots of noise. lots of cars going in every direction. >> he backed up. he took off, came around here and went on down the highway. >> i knew he saw me and i didn't want to get hit, so i pulled off. >> it was another terrorist attack on american soil. july 16th in chattanooga, tennessee. the killer was this man, 24-year-old mohammad youssuf