Prison inspectors exposed yesterday the shameful effects of government cuts after a London jail was found to be understaffed, overcrowded and infested with vermin.

HM Inspectorate of Prisons inspectors found that cuts at HMP Pentonville in north London was having "serious consequences" on staff and inmate safety, with high levels of drug use among prisoners and wardens losing track of prisoners' whereabouts.

The inspectors said that around 1,236 men were held in the prison at the time of the unannounced inspection last summer - 35 per cent above its normal accommodation level.