Violence behind bars is getting worse, according to the latest official figures, with incidents of assault and self-harm reaching record levels.
There were more than 26,000 assaults in prisons in England and Wales last year - an average of 70 a day.
Assaults on jail staff have risen to 6,844, up almost 40% on 2015, statistics released by the Ministry of Justice show.
Deaths in custody rose to 344 for the 12-month period to March this year.
Attacks on staff are continuing to rise, with the number of serious assaults trebling since 2012.
Surging levels of violence behind bars have prompted fears of a safety crisis, with a number of major disturbances in jails in recent times.
In one example a 12-hour riot broke out at HMP Birmingham in December, during which staff were pelted with missiles and paint.