julie banderas is here with someone who just crossed the finish line when it exploded. >> hi, guys. we're here with tom, a race official with the boston athletic association, in charge of the finish line. he was there when these explosions occurred. a beautiful day, people from all the world come to run and you were waiting for your family members. then what happened? >> what happened was i was on the finish line because i am in charge of the line and i decided to walk down to see my brother who was waiting for his oldest daughter at the corner of exiter and boyleton. as i started down the street, i was probably on a diagonal, 25 yards to my right, and maybe five yards back from the direct interest of the lens crafter when the horrific blast occurred. it moved me to my left. i thought i was going to fall and i didn't. but i looked back to my right, i