Police say youngsters using the Noble's Park skate park could have been put in danger.
Officers are condemning vandals who caused damage, sometime between Sunday lunchtime and Monday morning.
Sharp nails and planks of wood were used in an attempt to increase the size of the ramps, causing damage and making the area dangerous.
There's an appeal for witnesses and anyone who can help the investigation is asked to ring Police Headquarters on 631212 or the anonymous Crimestoppers line, on 0800 555 111.
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