Analyzing Ministry of Justice data, the inspecting body said that prison assaults increased by 27 percent to over 20,000 in 2015, with a 31 percent rise in serious assaults in the same period.
Self-harm incidents increased 25 percent in 2015, while self-inflicted deaths were up 27 percent between April 2015 and March 2016 compared to the previous period, amounting to a total of 100. The number of homicides in the 2015-2016 period increased from four to six, according to the independent inspectorate.
"Despite the sterling efforts of many who work in the Prison Service at all levels, there is a simple and unpalatable truth about far too many of our prisons. They have become unacceptably violent and dangerous places. A large part of this violence is linked to the harm caused by new psychoactive substances (NPS) which are having a dramatic and destabilising effect in many of our prisons," Clarke was quoted in the statement as saying.
The chief inspector added that methods used to tackle the existing problems were inadequate, stressing that the current system places drug abuse and mental illness sufferers into detention instead of carrying out professional assessments and treating the prisoners.
In February, former UK Prime Minister David Cameron called the country's prison system a "scandalous failure" and set out reform plans to increase prison governor autonomy, increase the qualifications of prison staff and try reducing the prison population.
