The governor of a Devon prison has said an investigation is under way, after three inmates staged a rooftop protest. The men climbed on top of buildings at Channings Wood Prison in Newton Abbot on Monday afternoon.
The last of the prisoners was talked down just before 0100 on Tuesday and staff throughout the area were called in to help with the incident.
Trained negotiators spoke to the protesting prisoners throughout their rooftop demo.
Governor Nick Evans said: "What we clearly need to do is find out how to stop another incident."