SCOTLAND’S jails stand “simmering on the brink of a crisis” amid a “near-record prison population,” the head of the Scottish Prison Service (SPS) has warned.

Writing in the Scotsman newspaper, Teresa Medhurst said that while recent early release schemes for short-term prisoners had managed to bring numbers to “roughly 100 below the level of two years ago,” there was still “severe overcrowding.”

“Sadly, that benefit has been lost amid the sharp increase we have seen in long-term prisoners — those serving more than four years — which is now around 600 higher than it was two years ago,” she said.

The SPS chief executive said that numbers had now “grown way beyond the level prisons were built to hold,” placing ever greater “risks and strain” on prison officers.

Paying tribute to those staff faced with a “myriad of challenges around serious and organised crime, illicit substances, mental health and trauma,” she applauded their “truly remarkable” efforts.

But in a stark warning, Ms Medhurst added: “Let me be clear. Our prisons are simmering on the brink of a crisis that threatens to overwhelm us and the communities we work so hard to protect.”

Her remarks followed the Prison Officers Association (Scotland) telling MSPs that the rising number of prisoners was the key problem facing jails.

Appearing before Holyrood’s criminal justice committee, assistant general secretary Phil Fairlie said any action to tackle the the pressure would “make a huge difference” in improving standards.

“We don’t have the time or the space or the human resource to manage what we’ve been asked to manage and so everything has taken a hit at the moment, everything is being done less well than we are capable of doing and are used to doing,” the union official added.

Praising the “incredible work of SPS staff whose dedication is shown in the exceptional care they provide in complex situations,” SNP Justice Secretary Angela Constance responded: “Scotland is not alone in facing challenges as a result of a rise in the prison population.

“There is no single reason for the increase and there is no single solution.

“We have taken a range of actions to address the issue and continuing to work with the SPS and partners on further measures to manage the complex prison population in a sustainable way.”