A prison roof has been set alight by an inmate who stripped off and torched his clothes.
Firefighters were tackling the blaze in the early hours of Saturday after the prisoner scaled the roof at HMP Guys Marsh, near Shaftesbury, in Dorset.
It is believed the inmate was wearing a "couple of sets of clothes" when he clambered up there during disruption at the Category C prison on Friday evening.
Around 60 inmates were taken to a secure area in the prison while the fire was tackled and the scale of the damage ascertained.
A Prison Service spokesman said: "Staff are responding to an ongoing incident involving one prisoner at HMP Guys Marsh.
"There is no danger to the public and staff are working to bring the incident to a safe conclusion as quickly as possible."