Projectile May News Today

Fbi forensics team to help determine what happened here. you see in the red circle here that white impact mark? well the head of the ntsb believes that that mark came from a projectile that hit the train before the derailment. and now look at this. it may be one of three trains that was struck on tuesday night. erin mclaughlin is following the investigation live from philadelphia. what have you learned this morning, erin? >> well in addition to the windshield you were just describing there, inve...