Authorities in the United States are tracking clues at the site of a suspected truck bombing in Nashville which saw at least three people injured early on Christmas morning.
Police initially attended the scene after gunshots were reported, but within half an hour, the parked camper van blew up.
The blast damaged dozens of homes and businesses, turning popular tourist areas into a scene resembling a war zone.
Authorities say the attack was intentional and have speculated it was an act of terrorism.
