Riot officers have quelled a disturbance at HMP The Mount in Bovingdon.
The Ministry of Justice confirmed the incident had been resolved by around 5pm.
It follows a second day of violence at the Hertfordshire Category C male prison.
READ MORE: Short-staffed HMP The Mount has ‘all the ingredients for disorder' according to new report
SEE ALSO: More trouble at The Mount as 'armed' prisoners storm wing
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