Nashville explosion knocks communications offline

Police evacuated nearby buildings and called in the bomb squad, shortly before the RV exploded.

Surveillance video shows the vehicle that was involved in the blast. Picture: Metro Nashville Police/AP

The Christmas morning blast in the US city of Nashville caused widespread communications outages which affected police emergency systems and grounded holiday travel at the local airport.

Metro Nashville police chief John Drake said officers had been responding to a report of shots fired early on Friday when they encountered a camper van blaring a recorded warning that a bomb would detonate in 15 minutes.