Glyn Travis, Assistant Secretary of the Prison Officers' Association (POA) said today's disturbance was "no surprise" to the POA.
"It's all down to chronic staff shortfalls and a management that are hell-bent on delivering things they can't deliver safely. Prisoners are saying 'We're not dealing with this'. "They will react."
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Ryan Evans' father says he wants his son to be a reminder to others of the dangers of swimming in open water.
Showery rain clearing tonight.
Outbreaks of rain clearing, feeling fresher. Sunshine and showers Tuesday.