"In the year ending 31 March 2015, there were 299 arrests for terrorism-related offenses, an increase of 31% compared with the previous year and the highest number since data collection began in September 2001," the ministerial department stated.
Previously, the highest number of terrorism-related arrests, 246, was recorded in the year ending March 2006, covering the period in which the 7 July 2005 London bombings occurred, claiming the lives of 52 people, according to the statement.
Over the past three years, an increasing number of UK citizens have been arrested on terror-related charges. In 2014, they accounted for 78 percent of all those arrested, compared with only 52 percent in the year ending March 2011, the Home Office said.
Since the act entered into force, the UK police have detained about 3,000 people related to terrorism, according to the Government statistics.
In March, a UK parliamentary report revealed that the number of Britons joining the Islamic State and other extremist groups is growing.
Over the recent months, the issue of countering extremism has been high on the European agenda, especially in the wake of January's Islamist shooting in France at the office of the Charlie Hebdo magazine, which claimed the lives of 12 people.