HMP Bedford Tornado team quells unrest at 'dungeon' jail
A specialist riot unit was sent to a six-hour disturbance in a prison which regulators had compared to "a dungeon".
The Tornado team was deployed at HMP Bedford after the incident was reported at 14:35 GMT on Saturday, said the Prison Service.
It was contained to one wing and resulted in no injuries to staff or prisoners, it added.
HMP Bedford was put into special measures in May after concerns over living conditions and violence levels.
A riot at the same prison in 2016 involving 230 prisoners caused £1m of damage to two wings.
Police cars were seen outside the prison on Saturday, although their attendance was precautionary and officers did not go in.
The incident was resolved by 21:00 GMT, the Prison Service said.
A Prison Service spokesman said: "We do not tolerate violence in our prisons and, where incidents like this occur, will always push for the strongest possible punishment for those involved."
A report from the prison's independent monitoring board in October said prisoners had effectively taken control at the 487-capacity men-only jail.
It found that prisoners regularly ignored rules; the smell of drugs was "pervading" some wings; and the segregation unit had a "consistent infestation of cockroaches and a plague of rats".
"The unit is simply appalling. It is a dungeon. These are not appropriate conditions in which to detain prisoners in the 21st Century," the report said.