Work on the building was due to take place to enable children to use it
An investigation has been launched after a building within Arrasey Plantation was set alight.
Police believe it's a case of arson and happened over the past few days.
On social media, officers have described the situation as 'saddening'.
Anyone with information is asked to contact headquarters on 631 212.
Government defeated as Tynwald rejects North and West Area Plan
Child First Policy hailed a good first step by Tynwald Youth Select Committee
Enterprise minister apologises again for 'foot in mouth moment'
Tynwald begins debate on controversial North and West Area Plan
