"In the year ending 30 June 2018, 100 persons were tried by CPS CTD for terrorism-related offenses, an increase of 28 (39%) from the 72 persons tried in the previous year. This latest year saw the highest number of persons tried, and highest number of convictions, in a single year since the data collection began in 2009," the bulletin read.
According to the bulletin, as of June 30, the majority of those in custody – 82 percent – were described as having Islamist extremist views, and 13 percent as holding far right-wing ideologies.
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The remaining prisoners are said to hold other ideologies, including those of groups related to Northern Ireland, such as the Ulster Volunteer Force paramilitary group.
Last year, the United Kingdom suffered a number of terror attacks, including a deadly attack in Manchester in May, which killed 22 people and injured hundreds more.