Padlocks from doors at three Pembrokeshire County Council let units at Tenby Harbour were removed causing damage to the locks sometime between 2 pm on Tuesday, March 3, and 8.30 the following morning.
No items were removed and there was no evident that access was gained to the units.
Police are reminding the public to take responsible actions to protect their property and report to police any suspicious behaviour in the harbour area.
Anyone with information about last week's criminal damage is asked to contact PC378 Lynsey Williams at the town's police station on 0845 330 2000.