Prison bosses have blamed Scotland's overcrowded jails for high levels of violence involving inmates and staff.
The prison service has failed to meet targets to reduce violence
The annual report of the Scottish Prison Service has revealed that the organisation has failed to meet targets aimed at reducing assaults.
In the past year, 29 members of staff were seriously assaulted, which was 16 more than the target figure.
A total of 127 prisoners were also the victims of assaults - 44 more than the target.
Over the same period, record levels of imprisonment have pushed the average
daily prisoner population to 6,475 and put Scots jails "at full stretch".
The report revealed the high levels of prison violence have been partly caused by overcrowding.
It also said that the high number of prisoner assaults is "perhaps not surprising considering the pressure of high prisoner numbers and the
subsequent pressure on accommodation experienced during this period".
Elsewhere, the report said that the SPS failed to meet its target for drug taking in prison.
About 83% of prisoners tested were drug-free, below the target of 85%.
The long-awaited review of Scotland's prison estate by the Scottish Executive was also blamed for leading to "an element of uncertainty" over the future of some of the country's jails.
The report added: "Now that the review has been concluded, the service has a clear idea of where it needs to invest and what it needs to do to provide a competitive business and demonstrate value for money to the Scottish
An executive spokesman said that two new prisons were being built to cope with the rising prison population.
He said: "We make no apology for a system that sees serious criminals serving serious time for their serious crimes.
"However, imprisonment is not always the best option for less serious offenders and our criminal justice strategy includes an increasing range of tough, high quality non-custodial options available to our courts.
"Assaults that take place within prison are as unacceptable as assaults that take place anywhere else."