A massive rammy at Perth Prison cost taxpayers nearly £40,000 in repairs, it has emerged.
Rioting inmates set fire to a pool table at the jail’s C-Hall, prompting an evacuation.
The wrecking spree, led by convicted killer Kristopher Marshall and fellow prisoner Ronald Smith, was eventually brought under control by officers in body armour.
Now figures released by the Scottish Prison Service show that the incident resulted in more money being spent on repairs at HMP Perth than any other jail in the country last year.
Perth’s repair bill jumped from just £436 in 2015/16 to £39,203 in 2016/17 – a rise of nearly 9,000%.
The figures released following a freedom of information request reveal that nearly £120,000 was spent repairing damage caused by inmates throughout the SPS estate in the last 12 months.
No money was spent on repairs on Castle Huntly in the last five years.
A SPS spokeswoman confirmed that the most recent repair bill for Perth was almost entirely down to the ruckus in C-Hall.
The shock rise in costs, which prison bosses initially thought was a mistake, has been described as a cause for concern.
Mid-Scotland and Fife MSP Alexander Stewart said: “Obviously there has been a sharp rise in costs for repairs which has caused a spike in the system.
“Although this doesn’t appear to be a trend, an increase like this will cause alarm for the staff and the inmates at the prison, as well as the authorities.
“Incidents causing a spike in this way does lead to cause for concern and I hope the matter will be fully investigated.”
A Scottish Prison Service spokeswoman said: “We have to ensure our prisons are in a good state — and have a duty to repair damage.”
Last year, Perth Prison was named the most violent in the country after a study revealed the rate of attacks soared to a five-year high of 13 throughout 2015/16.
The country’s biggest jail, Barlinnie, only recorded six incidents in the same time period.
The fracas in C-Hall kicked off in May 2016.
Police in riot gear were scrambled to the Edinburgh Road compound after two inmates attacked staff, before setting fire to a pool table.
Other prisoners were evacuated when Marshall and Smith staged a stand-off in the smoke filled wing.
The pair were later sentenced to a further four years beyond bars.