Authorities suspect arson in a fire last week that caused at least $10,000 damage to St. John the Baptist Catholic Church in Custer.

Custer Volunteer Fire Department Chief Joel Behlings said crews responded to a report of smoke at the building about 4:30 p.m. Thursday and discovered a fire smoldering on and around the church's altar.

Crews focused on ventilating the building at 449 Harney St. in Custer because the fire was mostly extinguished. Behlings said it appeared somebody had already tried to extinguish the fire.

He said the fire damaged the church's altar and an area behind it. A banner that was hanging above the altar was also burned.

Behlings said the altar will likely cost at least $10,000 to repair. He said the top and sides of the altar were both partially burned.

"It's definitely going to take some substantial work to repair it," he said.

The banner will cost the church about $1,200 to replace, Behlings said.

He said arson is the suspected cause, but authorities don't have any suspects and have not made any arrests. The fire was noticed by tourists who stopped by the church to see if there were any Masses that day, Behlings said.

He said people were working in the building earlier in the day, but the workers left and the building was unlocked and empty before the fire.

The fire is under investigation by the Custer Volunteer Fire Department, the Custer County Sheriff's Office and the state fire marshal.

Behlings said his crews ventilated the building after the fire to clear the smoke. Services were still held at the church Saturday night and Sunday morning, he said, but the church "still had a burned smell."

The church's pastor, Rev. Peter Kovarik, did not return phone calls Monday for comment on the fire.

Contact Ryan Woodard at 394-8412 or ryan.woodard@rapidcityjournal.com