Inmates “threw paint and smashed fire alarms” during a disturbance at a young offenders institution.
The Prison Service said four prison officers suffered minor injuries in the trouble at HMYOI Aylesbury in Buckinghamshire.
Inmates “trashed” E Wing in protest over a lack of showers and time out of their cells, the BBC was told.
The Prison Service said: “Offenders who behave in this way will be punished and may face extra time behind bars.”
A woman whose partner is an inmate told the Us some of the men had leapt on to the wing’s safety netting and refused to come down.
The source said her partner was not involved and went back to his cell. Another prisoner sent pictures of the disturbance from a banned mobile phone.
“There’s a new regime and they aren’t allowed any association during the week,” she said.
“So they can shower and exercise but then have been locked up all week. They had one shower on Monday and nothing since.
“On Saturday they weren’t allowed the weekend association where they can play pool, etc. This morning, they were allowed another shower but, when they were told they were going to be locked up again, with no explanation, lots of them refused to go back.”
The inmates then “trashed the wing”, the source said, adding “they’ve thrown paint, smashed fire alarms and broken cameras”.