Labour MP for Bedford Mohammad Yasin called for improvements to Bedford Prison during a debate in the House of Commons.
Prisoners at a jail are having to sleep with protective mouth covers to prevent cockroaches crawling in while they sleep, an MP has claimed.
Labour MP Mohammad Yasin spoke out about dirty conditions in Bedford Prison in a House of Commons debate.
The category B prison was issued with an urgent notification to improve in November, after inspectors from HM Inspectorate of Prisons (HMIP) found violence, squalid conditions and high rates of self-harm.
Mr Yasin said to MPs: "I have been told that prisoners sleep with covers over their mouths to stop cockroaches crawling in while they sleep.
"The inhumane segregation unit, once described as a rat-infested dungeon, was supposed to have been shut down years ago, but endless delays to the new unit means it is still in use.
"So will the minister explain what he believes prisons are for?
"Locking people away in these conditions does not keep society safe.
"Where is the rehabilitation in this system?
"Who can leave these conditions a better person, or less likely to reoffend?
"Overcrowded, squalid, and unsafe prisons will never help or allow people to turn their lives around and move on from a life of crime and hurting others."
The MP is urging ministers to set out plans to improve the prison, suggesting huge investment and moving inmates to other institutions to tackle overcrowding.
The inspection found levels of violence against staff in Bedford Prison were at the highest rate in any adult male prison in the country, while it had the third highest rate of recorded self-harm.
It also found new prisoners being placed in dirty cells with three quarters of inmates lived in overcrowded conditions with a widespread infestation of rats and cockroaches.
During the Commons debate justice minister Edward Argar said he was "deeply concerned" by the inspectorate's findings.
He added: "I have been clear the situation needs to improve quickly.
"This is the second time an urgent notification has been invoked at HMP Bedford, and I agree that the circumstances leading to this are not acceptable."
His boss, Justice Secretary Alex Chalk, is due to respond to the HMIP inspection by 15 December.
This will include a plan to address the conditions and staffing problems facing the prison.
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