Vandals may have used gasoline to try and burn playground equipment, leading to the temporary closure of a part of Optimist Park.
The playground area will be closed while Billings parks officials work to replace damaged parts that were burned.
"We've had someone try to torch the playground and damage a third of the playground equipment," said Mike Whitaker, director of Billings Parks and Recreation. "You wouldn't think that playground equipment would burn, but it appears someone used gasoline."
The parks department fenced off the playground area to be repaired. The badly burned parts will be removed, Whitaker said, and they will "retrofit what's left."
Plastic parts were especially vulnerable to the vandalism, he added.
The incident has been reported to police, but Whitaker hasn't heard of any suspects. Parks officials have ordered the parts needed for repairs.
"As soon as we get those parts in, we will make the changes and reopen the playground," he said.