Lives are being put at risk by vandals who are throwing lifebuoys into the sea, Jersey Coastguard has warned.
Three lifebuoys have been removed at the north end of St Helier Marina twice this month.
Jersey Coastguard said such incidents had been a "regular occurrence for a number of years".
Deputy Harbour Master, Captain Peter Moore, said had his team not discovered the loss and quickly replaced the lifebuoys "lives could have been lost".
Jersey Coastguard said the second incident this month happened on the evening of 14 February when members of the public reported seeing a group of youngsters throw a lifebuoy into the marina.
Replacing the lifebuoys or damaged boxes costs £100 each.