Government figures have shown a sharp rise of Covid-19 cases in the St James's Park & Hoopern area, reflecting an outbreak reported at Exeter Prison.
The Ministry of Justice confirmed to DevonLive on Tuesday that the prison was taking steps to control cases among both staff and inmates.
Prisoners are reportedly been confined to their cells and refused activities such as showers, exercise and visits - leading to an outcry from their friends and loved ones.
Exact coronavirus numbers have not been confirmed, but Devon County Council's figures show a sharp spike in confirmed cases in Exeter on Thursday, February 11 and Friday, February 12.
Positive tests leapt from nine cases on Wednesday, February 10 to 29 the following day. There was a slight decline, to 22, on February 12, before dropping to six on Saturday, February 13.
And Government figures have now backed this up, with a sharp rise in the St James's Park & Hoopern area where the prison is based.
Data showed a jump to 37 cases with cases from February 11 included - up from 14 the day before and significantly above the five reported yesterday.
That spike has been enough to leave Exeter as one of just 16 places in England where coronavirus infections are rising.
Data from Public Health England states that 95 per cent of local authorities have seen a fall in cases in the last seven days.
Exeter's infection rate has climbed from 30.4 cases per 100,000 people to 79.1, while Devon has seen a rise over the same period of time to 64.9 per 100,000 people, having been 55.4.
If the figures for St James's Park & Hoopern are taken out of the equation, Exeter returns to having one of the lowest infection rates in England.
After being contacted by DevonLive, a prison service spokesperson said: "Our priority is to limit the spread of the virus and protect the lives of those who live and work in our prisons.
“We have taken precautionary measures at Exeter, in line with public health guidance, and will continue to closely monitor the situation.”
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