Arsonists set alight a traffic cone in the bandstand in the Ripon Spa Gardens, causing damage to the bandstand floor.
The fire was set at approximately 6.30pm on Monday, January 19, and firefighters were called to help extinguish the blaze.
Ripon police are appealing for information and are asking witnesses to come forward.
“We are conducting enquiries and are requesting the public’s assistance to help determine the full circumstances surrounding the incident,” said a spokesman for North Yorkshire Police.
“Anyone who was in the area at the time and witnessed the incident or has any information about those responsible is asked to contact the police.”
Anyone with information is asked to call North Yorkshire Police on 101, selecting option two and asking for Wayne Hutchinson.
You can also email firstname.lastname@example.org.
To remain anonymous, contact Crimestoppers on 0800 555 111.
Quote reference number 12150010878.