Approximately 200 inmates in Bedford Prison rioted on Sunday, a massive disruption that took riot officers more than six hours to disperse. The Guardian reports that the Prison Service has launched an investigation into the riot, which began shortly after 5 p.m. local time. 

A representative for the British Prison Service told The Guardian that riot officers were brought in to break up the riot:

Specially trained prison officers and staff from the emergency services have successfully resolved an incident involving a number of prisoners at HMP Bedford. An investigation into this incident will take place. We are absolutely clear that prisoners who behave in this way will be punished and could spend significantly longer behind bars.

The riot was anticipated by prison officials to some degreeSteve Gillan, general secretary of the Prison Officers Association​, told the Guardian. "The POA [Prison Officers Association] has been warning about this situation of violence in our prisons—it would appear it’s coming to fruition. I just hope there’s no prisoners or indeed prison officers injured in the violence," he said.

The BBC reports that recent investigations into Bedford prisons revealed that prisoners found it "easy" to obtain drugs, and very difficult to get bedding or clothes. The percentage of prisoners who had developed a drug problem after entering prison went from 4 percent in 2014 to 14 percent in the recent investigation. Instances of self-harm have risen from 67 reports in 2014 to 121. 

The UK is set to invest £1.3 billion (around $1.6 billion) in prisons over the next five years.