HMP Dartmoor, a category C men's prison in Devon, is being temporarily closed due to the discovery of high levels of radon, a radioactive gas that is a leading cause of lung cancer. Around 175 inmates will be relocated over the next two weeks, exacerbating the strain on an already overcrowded prison system. This closure highlights the ongoing crisis within the UK prison estate, prompting the Government to take urgent actions, including adjusting regulations to reduce the sentence time before automatic release for certain prisoners. Built in the early 19th century, Dartmoor had previously been slated for closure in 2023 but remained operational due to rising prisoner numbers. Legal advice is being sought by staff and inmates over potential exposure to the gas. The Ministry of Justice underscores the need for new prison places to manage the most dangerous offenders and ensure public safety.