“Immediate action” is being taken after blueprints of prison layouts were shared online.

The maps detailing the layouts of prisons in England and Wales have been leaked on the dark web in the past two weeks, according to The Times.

The detailed information is said to include the location of cameras and sensors, raising fears they could be used to smuggle drugs or weapons into prisons or help inmates plan escapes.

Security officials are now working to identify the source of the leak and who might benefit from the details.

The Ministry of Justice did not disclose which prisons were involved in the breach.

A government spokesperson said in a statement: “We will not comment on the specifics of security matters of this nature, but we are aware of a data breach of the prison estate and, as with any potential breach, have taken immediate action to to ensure that prisons remain safe.”

The leak comes in the middle of a chronic prison overcrowding crisiswhich has led to early release schemes and security risk recategorisation for some offenders to ease capacity pressures.

Minister of Justice Shabana Mahmood launches a sentencing review in an attempt to alleviate the crisis.