NASHVILLE, Tenn. (WKRN) — A large explosion was reported in downtown Nashville early Christmas morning.

The explosion happened in the area of Second Avenue and Broadway near Commerce Street occurred around 6:30 am Friday. Heavy black smoke could be seen rising above the affected area.

At least three people suffered non-life-threatening injuries and were transported to local hospitals, the Nashville Fire Department said. Mayor John Cooper said all three are in stable condition.

MNPD, FBI, and ATF are investigating the explosion of an RV outside 166 2nd Avenue North downtown. 

PHOTOS: Large ‘intentional’ explosion in downtown Nashville

Officers responded to a call of shots fired call on 2nd Avenue at approximately 5:30 a.m. The department’s Hazardous Devices Unit was called to check the RV.  As those officers were en route, the vehicle exploded outside an AT&T transmission building. Multiple buildings on 2nd Avenue were damaged, some extensively.

Metro Nashville Police Department’s spokesperson, Don Aaron said police believe the explosion was an intentional act.

The Associated Press is reporting authorities have found human remains in the vicinity of the explosion in downtown Nashville.

“We have found tissue that we believe could be remains,” John Drake, Chief of Police Metro Nashville Police Department said in a Friday evening briefing, but wasn’t able to confirm if a body was found.

Metro Police have released a photo of the RV that exploded Christmas morning in Nashville.

“Officers encountered an RV that had a recording saying that a potential bomb would detonate within 15 minutes. Upon hearing that, officers decided to evacuate the buildings nearby,” Drake said. “Shortly after that the RV exploded.”

AT&T is experiencing service outages across Middle Tennessee and Kentucky. Service outages are including TV, phone, and internet customers. The outages are affecting local 911 systems across the area. You can find alternative numbers for some of the emergency services here.

Mayor Cooper signed Executive Order 12 on Friday to issue a state of civil emergency for parts of downtown Nashville. The area including James Robertson Parkway, 4th Avenue North, Broadway, and the Cumberland River will be under curfew starting at 4:30 p.m. Friday and extending until 4:30 p.m. Sunday, December 27.

The Department of Justice released the following statement:

“Acting Attorney General Jeff Rosen was briefed on the Nashville incident early this morning and directed that all DOJ resources be made available to assist in the investigation.”

The White House also released the following statement:

“President Trump has been briefed on the explosion in Nashville, Tennessee, and will continue to receive regular updates. The President is grateful for the incredible first responders and praying for those who were injured.”

President-Elect Joe Biden’s Office released the following statement:

“President-elect Biden has been briefed on the explosion in Nashville, TN. The president-elect and Dr. Biden thank all the first responders working today in response to the incident, and wish those who were injured a speedy recovery. “

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Anyone with information about this case is asked to contact Crime Stoppers at 615-742-7463.

The FBI has also established a digital tip line for anyone with information about the explosion. Those who prefer to call can do so by dialing 1-800-CALL-FBI.