Chaos ensued at Ranby prison in Retford as prisoners took control of a whole cell block during an eight-hour riot.
The disturbance began just after 12:30pm on Saturday 26th July, when 60-70 prisoners began rioting after refusing to return to their cells.
It is understood the riot began when the prisoners were not allowed outside in the hot weather.
At around 6.40pm, Glyn Travis, assistant secretary of the POA, confirmed that prisoners had taken control of a unit at the jail.
He said: “120 prisoners refused to return to their cells this afternoon. They have taken control of a unit.”
“We have national resources at the prison trying to establish a surrender plan.”
At 7.30pm firefighters and prison officers carrying shields entered the prison, before prisoners were seen being transported away in escort vans.
The riot was officially confirmed to be over at around 9.30pm, with no reports of any injuries to staff or prisoners.
The Ministry of Justice said: “The disturbance at HMP Ranby has ended safely. No staff or prisoners injured. Visits tomorrow will take place as normal.”
The incident came just weeks after MP for Bassetlaw John Mann highlighted deteriorating conditions at the prison, as well as the issue of four people committing suicide there in the past year.
He said: “These issues have been raised with the prison governor, the Ministry of Justice and the prisons minister in 2011 and 2012.”
“These warnings have been ignored, including the specific warning that the management of Ranby was in chaotic meltdown.”
Speaking after the disturbance, Mr Mann said: “Along with others, I warned the Government about the staff shortages and conditions at Ranby Prison.”
“They carried on with their staff cuts, and there are now 88 fewer staff working at the prison than there were in 2010.”
“This has led to worsening conditions and safety at the prison and Saturday’s riot shows just how bad things are now.”
“The Government now has to urgently act to increase the number of staff and improve safety at the prison.”