The Department of Home Affairs says the prison has almost 15 per cent more inmates than it was designed for.
A Freedom of Information request asked how many prisoners the Jurby facility was designed to hold, and how many people were currently incarcerated there.
In its response, the department said the official capacity was 141 - and on April 7 there were 159 inmates.
It added there were 26 cabins on top of the permanent accommodation, all of which were being used.
Bus services north and south face disruption later
Bus Vannin says a number of its services may face disruption this evening.
Wildlife Trust unveils woodland plans
The Manx Wildlife Trust has submitted a planning application for a new woodland in the northeast of the Island.
Deadline looms for by-election nominations
Time's running out to get your forms filled in if you'd like to stand as a commissioner in Marown.
Biker in UK hospital after Mountain crash
Police are appealing for witnesses to come forward after a crash on the Mountain Road yesterday afternoon.
Trial event closes roads in Peel and Ramsey
There'll be road restrictions in Peel and Ramsey during a motorsport event this weekend.
Requisition meeting for Garff voters
A requisition meeting will be held in Maughold next month.
Castletown police station could be yours... for £250,000
Fancy owning a landmark building in the south of the Island?
Brewery advertising for operator for landmark Laxey pub
Could you run one of Laxey's best-known pubs?
