The situation at a covid hit prison has been described as close to "boiling point" after two prisoners died within the space of 14 days while four are being treated in hospital.
Staff at HMP Risley in Warrington told the ECHO they fear for their safety at work.
The Ministry of Justice says it has been dealing with outbreaks of the virus in two wings but says there are currently "less than a dozen active cases".
The ECHO understands two inmates from the Category C men's prison, one in his 40s, died at Warrington Hospital over the past fortnight after being taken in with "breathing difficulties".
Four prisoners are being treated in hospital, although they are not understood to be in intensive care.
A spokesman for the prison service confirmed the deaths but said: "It is rightfully for the coroner to determine the cause of death."
A source told the ECHO: "It is tense on the wings, it is like reaching boiling point.
"Staff are going off sick which impacts on staffing levels, which were already under pressure before covid.
"It is worrying, you do fear for your safety going into work."
An MOJ spokesman said there had been no positive covid tests among prisoners or staff within the past seven days.
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They 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 Risley, in line with public health guidance, and will continue to closely monitor the situation."
