Possible human 'tissue' at Nashville blast site

Authorities on Friday said investigators have uncovered what could be possible human remains after a vehicle explosion rocked Nashville, Tennessee on Christmas morning in what police say may have been a quote "intentional act."

Nashville Police Chief John Drake.

"We have found tissue that we believe could be remains."

Police had earlier said it was uncertain whether anyone was inside the recreational vehicle when it exploded.

The parked motor home exploded in downtown Nashville early Friday morning minutes after a recorded announcement emanating from the vehicle warned of a bomb.

The recorded voice warning, shared widely on social media, said quote: "This area must be evacuated now. If you can hear this message, evacuate now."

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

Officers quickly went door-to-door in nearby buildings to hustle people to safety, and called in the bomb squad, which was on its way to the scene when the vehicle blew up.

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

Fire officials said three people suffered minor injuries.