Northumbria Police are appealing for information after a climbing frame was set on fire in Pegswood, near Morpeth.
Between 7.30pm and 8.20pm on Monday, May 11, vandals set fire to a climbing frame in the park area of Welfare Field.
The fire was extinguished by Northumberland Fire and Rescue Service, but it damaged the play equipment and the nearby grassed area.
The damage will cause thousands of pounds to repair and inquiries are ongoing to identify those responsible.
Anyone with any information is asked to contact police on 101 ext 69191, quoting reference number 55913/05/15.