Council leader David Christian says CCTV footage shows a recent spate of vandalism is down to one group of youngsters.
He was speaking out after the public toilets on Loch Promenade were set alight and Shaw's Brow car park damaged in recent weeks.
Mr Christian says Douglas Council will work as closely as possible with officers to make sure those responsible answer for their behaviour.
And he appealed to parents to know where their children are during the evenings.
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