THERE has been a substantial increase in assaults in Dorset prisons over five years.

At HMP Guy's Marsh in Shaftesbury 211 assaults were recorded in 2017, of which 60 were on prison staff. In 2012, 69 assaults were recorded, meaning there has been an increase of 206 per cent.

At Guy's Marsh 22 assaults were defined as serious, a category which includes sexual assaults and those where victims required hospital treatment.

Figures from the Ministry of Justice also reveal that 172 cases of self-harm were recorded in Guys Marsh last year, compared with just 67 in 2012.

The rise reflects a national trend, which prison reform campaigners have dubbed a "national emergency".

At Portland Prison assaults doubled over the same period, from 153 in 2012 to 303 in 2017, of which 105 were on prison staff, 37 defined as serious. There were 188 cases of self-harm in Portland last year, compared with 70 in 2012.

Many prisoners from Dorset, particularly those on remand from Bournemouth Crown Court, are kept at HMP Winchester, which saw six times more assaults last year than in 2012. There 369 assaults were recorded in 2017, of which 170 were on prison staff and 32 were 'serious'. The 2012 total was 60.

Two self-inflicted deaths were recorded in Winchester in 2017, a definition which includes suicides and accidental deaths through self-harm, and there were 474 cases of self-harm at the prison last year, compared with 151 in 2012.

Assaults also doubled at immigration centre The Verne on Portland, where 65 assaults were recorded in 2017 compared with 27 in 2012. Of these, 12 were on prison staff and three were defined as serious. There was one self-inflicted death, and 37 cases of self-harm compared with five in 2012. The Verne closed in December and is due to be reopened as a prison.

Across prisons in England and Wales, nearly 30,000 assaults were recorded last year, more than double the number in 2012. Self-harm also increased by 92 per cent over the same five-year period, with nearly 45,000 cases in 2017.

Frances Crook, chief executive of the Howard League for Penal Reform, said: "This shameful rise in violence and self-injury is the direct result of policy decisions to allow the number of people behind bars to grow unchecked while starving prisons of resources.

"This is a national emergency, and the government must respond boldly and urgently."

Justice Secretary David Gauke said "urgent action" was being taken to address the problem.

"Assaults on our hardworking staff will never be tolerated. We are ensuring prison officers have the tools they need to do the job, rolling out body worn cameras, 'police-style' handcuffs and restraints, and trialling PAVA incapacitant spray."

He said "90 per cent of our additional 3,111 prison officers" would be "on landings by the summer".