Vehicle explosion rocks Nashville on Christmas

A vehicle explosion shook Nashville, Tennessee early on Christmas Day morning in what Nashille Police Department's Don Aaron described as an "intentional act."

"We do believe that the explosion was an intentional act."

Fire officials reported taking three people to the hospital, but none were critically injured.

Police reported seeing the vehicle when they responded to an emergency call of "shots fired" in the downtown tourist area in the early morning.

Without specifying what made it suspicious, police said 'circumstances' about the motor home prompted officers to call the bomb squad.

The bomb squad was on the way when the explosion occurred.

Andrew McCabe, a former deputy FBI director, told CNN an explosion of this size would be investigated as a possible act of terrorism, whether domestic or foreign.

Moments before the blast, police officers went door-to-door in nearby buildings to hustle residents to safety.

Police said it was not immediately clear if anyone was inside the motor home when it exploded.

Most of the buildings were closed given the hour and Christmas holiday in the heart of the city.

The explosion destroyed several other vehicles and damaged several buildings.