GALLATIN, Tenn. (WKRN) — Sumner County leaders are assessing damage to the new courthouse that caught fire Sunday night, and determining how long construction will be delayed.

The county broke ground on the building in April 2021, and it was set to open in 2023.

It caught fire at 8:02 pm Sunday, according to the Gallatin fire chief, likely due to a lightning strike. Firefighters had the flames under control in a little more than an hour.

📧 Have breaking come to you: Subscribe to News 2 email alerts

Investigators are still working to determine the fire’s official cause.

Sumner County officials announced Monday, the Tennessee Bureau of Investigation (TBI) has joined the investigation, which will bring additional resources to the table and speed up the process.

“This is going to be a laborious process —as they look for the cause and origin of the fire,” Chief Jeff Beaman of the Gallatin Fire Department said.

Luckily no one was inside at the time, so no one was hurt. In addition, no other surrounding buildings were damaged.

“That’s the big takeaway,” Anthony Holt, Sumner County Mayor said. “You can replace buildings, you can do a lot of things, but you can’t replace a life.”

The roof of the courthouse suffered the most damage, and roofing materials were on top of the building during the fire. County leaders believe they’ll have to replace around 30% of the roof. Since Sumner County doesn’t have the title of the building yet, insurance for Turner Construction, the company building the courthouse, is expected to cover the repair costs.

“I am confident this is going to turn out in the end where the taxpayers won’t end up holding the bag and we want to make sure we’re responsible and get the building constructed at cost if at all possible,” Holt said.

⏩ Read today’s top stories on wkrn.com

However, the county currently faces potential construction delays, depending on how long the investigation into the fire’s cause lasts. In addition, supply chain issues could impact the timeline.

Officials said it will take at least a couple of days until they have any new information.