On Christmas morning, an explosion rocked downtown Nashville, Tennessee and left at least three people injured and dozens of buildings damaged.

According to CNN, Metro Nashville Police Department officers responded to calls of shots fired on Friday morning (Dec. 25). They approached an RV that was parked in front of an AT&T building. Police did not find any evidence of shots being fired, but the RV looked suspicious and they called for a hazardous unit to investigate.

As they waited, the vehicle exploded around 6:30 a.m. local time. Three people were taken to a local hospital and thankfully, none of them were in critical condition.

Authorities believe the explosion was planned. “We do believe this to have been an intentional act,” police spokesman Don Aaron said. “Significant damage has been done to the infrastructure there on 2nd Avenue North.”

The force of the explosion knocked one police officer down and caused another to lose his hearing. None of the officers were seriously injured.

The FBI and ATF are now investigating the incident. The Tennessee Highway Patrol and local police have shutdown the area. President Donald Trump and acting U.S. Attorney General Jeff Rosen have been briefed on the explosion and will be given regular updates. Department of Justice resources will be made available to assist in the investigation.

A Philadelphia man who was staying in a nearby hotel described the explosion. “It was a very loud explosion,” said Joseph Fafara. “We tried to rationalize it that it was an earthquake or something. But it was obvious it wasn’t an earthquake.”

Buck McCoy, another eyewitness, says he heard gunfire before the explosion went off. “All my windows, every single one of them got blown into the next room. If I had been standing there it would have been horrible,” he told the Associated Press. “There were about four cars on fire. I don’t know if it was so hot they just caught on fire, and the trees were all blown apart.”