Marown Commissioners are appealing to the public after a large pile of grit and leaves was dumped on the cycle track by the football field.
They're asking anyone who might be able to identify the culprit to get in touch with the local authority.
The Memorial Playing Fields committee adds members put in a lot of their own time to maintain them, and it's not fair to expect them to deal with such incidents.
It happened on the evening of Tuesday, October 14.
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