New disorder has broken out at The Mount prison in Hertfordshire after riot police were sent in to quell a night of unrest.
That was before specialist teams of riot officers - equipped with shields and batons - were called to the jail on the outskirts of Bovingdon near Hemel Hempstead.
Alex Cavendish, a prison affairs academic and blogger, told the broadcaster: "The technical term is that the staff have lost control of two wings".
A MoJ spokesman said: "Specially trained prison staff have been deployed to HMP The Mount to resolve an incident involving a number of prisoners".
And it comes after several prisoners were involved in a lengthy disturbance across two wings at the same jail on Monday.
A Hertfordshire Constabulary spokeswoman said: "Following [Monday's] incident we are working with the Ministry of Justice and are now reviewing what, if any offences, have occurred".
Crédit du Maroc lance sa fenêtre participative sous l'enseigne "ARREDA"
Depuis le 20 juillet, les différentes banques de la place ont obtenu leur convention d'ouverture de Bank Al Maghrib. L'activité de banque participative a officiellement débuté au Maroc mercredi 26 juillet, rappelle Ecofin.
Yesterday's large-scale disturbance came as a report warned of staff shortages within the prison system - where HMP The Mount was listed as one of dozens marked a "concern".
The Category C male prison, which opened in Hemel Hempstead in 1987, has a population of more than 1,000 prisoners.
The report by the Independent Monitoring Board (IMB) also slated the category C jail for not dealing with a Spice epidemic.
It is understood that prisoners have seized control of part of Nash wing, which houses 250 inmates, including many who are serving short sentences with just months left to serve.
A spokesperson for The Ministry of Justice said: "The prison is completely secure and there is no risk to the public".
There were 24 vacancies in February and many staff working there had less than two years' experience, it added.
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