NASHVILLE, Tenn. (WKRN) — Nashville dispatchers fielded a series of chilling calls on Christmas morning as multiple gunshots were reported in the downtown area, followed by the detonation of a bomb inside of an RV.

The Nashville Emergency Communications Center released audio of six calls made to 911, the first of which came in just before 5:30 a.m. Friday regarding several rounds of gunshots fired in the area of Second Avenue North near Church Street.

“There have been three rounds of gunshots inside the building,” the caller whispered to the 911 operator. “First, about seven or eight minutes ago, and then about five minutes ago.”

The caller told the dispatcher he believed the gunshots were coming from “in the building,” but another caller nearby advised hearing “gunshots on the streets.”

“We’ve heard it happen three times now and each time, it sounds like it is six or seven shots,” the second caller told a 911 dispatcher. “It happened and then 30 minutes later it happened and then 20 minutes later it happened.”

Minutes later, another caller reported hearing a warning message coming from an RV parked near the location.

“We’ve got a recording out here saying there is a limited time to evacuate this area on Second Avenue North, downtown Nashville. Is that you guys?” the female caller asked.

She continued, “there is a recording out there saying there is a limited amount of time to evacuate this area, there is a large bomb inside this vehicle.”

Federal investigators said Anthony Quinn Warner detonated a bomb inside of the RV around 6:30 a.m. Friday, killing himself, injuring three others and damaging more than 40 buildings.

Another person called 911 just after 6:30 a.m. to report the explosion.

“It is at Second Avenue and I believe either Church or Commerce street. A massive [expletive] explosion downtown with a huge fireball,” he explains. “I’m at the Encore Apartments on the 15th floor. It shook all the windows.”

The caller continued, “I can’t see anything. I can’t see through the smoke right now to see exactly what building it is… Oh my God, that is terrifying. It looks like something is on fire still.”

Metro police and the FBI have not revealed if they believe the AT&T building where the RV was parked was Warner’s intended target, but said they are investigating.

Investigators are also working to analyze chemical residue from the scene and determine the chemicals that were used to make the bomb.

The FBI is working to compile a list of community resources to share with those impacted by the bombing. In the mean time, anyone needing assistance can contact the FBI Memphis Field Office or the Knoxville Field Office to speak with a victim specialist.

The Federal Bureau of Investigation is leading the investigation into the downtown Nashville explosion. Anyone with information should call 1-800-CALL-FBI or submit a tip by clicking here.