It's been confirmed that Dorchester Prison is to close and discussions are underway to end the lease at Dartmoor Prison.
Elsewhere, Portland's Verne Prison will be turned into an immigration detention centre.
The former Victorian military barracks, transformed into a jail more than 60 years ago, will become a Home Office immigration unit housing people waiting to be removed from the UK.
Duncan Sleightholme reports:
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Overcast and windy tomorrow for the South West and it will stay like that for a few days yet. Alex Beresford has the forecast.
A wet start and overcast at times tomorrow and that weather is likely to dominate for the next few days. Alex Beresford has the forecast.
A man has been arrested for threatening Gina Miller, the woman behind the Brexit legal challenge, over the internet.