Two men have been spotted on the roof of Swansea Prison.
Onlookers said the men were prisoners but this has yet to be confirmed.
Fire engines are at the scene but Mid and West Fire Service would not give any details of an incident. South Wales Police said it is not involved.
Bob Griffiths, from Bridgend, who saw the men on the roof said: “They are shouting at each other and the other prisoners are shouting from the cells.”
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