A vehicle exploded in the downtown area of the city of Nashville, Tennessee on Friday at around 6:30 a.m. local time (12:30 UTC).
Three people were injured in the blast. They were taken to hospital, but none of them were in critical condition.
Police are uncertain whether anyone was inside the RV at the moment of the blast.
Investigators found tissue that they “believe could be human remains,” Police Chief John Drake said at a briefing.
“We will continue to examine that,” Drake told reporters. “There are no fatalities we know of,” he added.
The blast also caused widespread damage to buildings as well as telecom outages due to a telecoms office being affected.
The area was largely deserted at the time of the explosion, due to the early hour and the Christmas holiday, when most businesses are closed.
“This appears to have been an intentional act. Law enforcement is closing downtown streets as investigation continues,” the Metro Nashville Police Department said.
How did events unfold?
Authorities responded to a report of shots fired on the scene, where they encountered a motor home, also known as a recreational vehicle, or RV. The RV was blaring a recording that said a potential bomb would detonate in 15 minutes.
This prompted the police to evacuate nearby buildings and call in a bomb squad.
“Shortly after that, the RV exploded,” Drake said in a news conference.
Mayor John Cooper issued a state of emergency for the city — known as a hub for American country music — and a curfew for the area.
Blast impacts telecoms firm
The detonation happened near an office of telecommunications company AT&T and caused a disruption in service.
“We do not know if that was a coincidence, or if that was the intention,” police spokesman Don Aaron said.
AT&T declined to say how widespread outages were.
The AT&T outages site showed service issues in middle Tennessee and the neighboring state of Kentucky. Several police agencies reported that their emergency 911 systems were down, including Knox County, home to the city of Knoxville located about 290 kilometers (180 miles) east of Nashville.
Eyewitness: ‘I got my cat in her carrier’
Local resident Betsy Williams told DW about her experience of fleeing her apartment ahead of the explosion.
After hearing what she described as “very loud” gunshots, she noticed a white RV parked right across the street.
“Coming from the RV was a computerized voice message saying, evacuate now, evacuate now. This vehicle has a bomb. It will explode, evacuate now.”
“Then it started on a countdown where it said this vehicle will explode in 15 minutes and then in 14 minutes. Then we started really gathering our things up, I got my cat in her carrier. I got my son who was staying in another apartment that was also overlooking Second Avenue.”
She told DW she thinks she would have been killed or severely injured if she had not left her apartment because she was sitting next to her window.
“We raised the window so we could really clearly hear what the RV was saying,” she told DW TV.
The eyewitness also praised the police for their quick response.
How did politicians react?
US President Donald Trump was briefed about the situation in Nashville, White House spokesperson Judd Deere said.
The Justice Department said Acting Attorney General Jeff Rosen was also briefed and had directed all department resources be made available to help with the investigation.
Tennessee Governor Bill Lee said on Twitter that the state is ready to provide the city with the resources necessary ”to determine what happened and who was responsible.”
“This morning’s attack on our community was intended to create chaos and fear in this season of peace and hope. But Nashvillians have proven time and time again that the spirit of our city cannot be broken,” Cooper said at a news conference.