More than one-third of the popular Belfast Bikes are currently out of action due to either theft or vandalism, Belfast City Council has said.
The council said a spate of theft and vandalism is jeopardising the future of the scheme.
As of yesterday, 210 of the 576 bikes in the fleet have either been stolen or have had to be taken out of service due to vandalism, which is costing the scheme almost £1,800 per month.
Over the Easter weekend, 19 bikes were stolen, six of which were recovered, and a further eight were vandalised.
Belfast’s Lord Mayor, Alderman Brian Kingston, added: “Belfast Bikes has enjoyed a hugely successful start-up period, and the popularity of the scheme clearly shows that we were right to back the initiative.
“But we have to address the problem of antisocial behaviour and put measures in place to safeguard the scheme.”
The PSNI has appealed for information about any theft or vandalism.