Syria-related terror arrests increased six-fold last year, fresh figures have revealed.
A total of 165 arrests were made by police officers across the country for offences including terrorist financing, commission, preparation or instigation of acts of terrorism, and attending a terrorist training camp, Scotland Yard said. This compares to 25 Syria-related arrests in 2013.
The number of arrests for terrorist offences totalled 327 in 2014, a 32% increase compared with the previous year.
Senior national co-ordinator for counter terrorism policing Helen Ball said: "Last year's arrest figures demonstrate a considerable increase in volume, range and pace of counter-terrorism activity in the UK.
"We have been running exceptionally high numbers of investigations, the likes of which we have not seen for many years.
"Several attack plots have been disrupted, of various sophistication, from individuals planning to carry out lone attacks to more complex conspiracies, the majority seemingly directed by or inspired by terrorism overseas.
"The partnership between police and MI5 is very effective, and we are experiencing very strong support from the communities.
"We will continue with this vital work to protect and work with the UK public to combat terrorism in all its forms."
The terror threat level in the UK was raised from substantial to severe last August against a backdrop of increasing concerns over hundreds of aspiring British jihadis travelling to Syria and Iraq to learn terrorist ''tradecraft''.
Fears of a terrorist attack on Britain's streets have heightened in the wake of the rise of Islamic State (IS), the extremist group that has taken over large swathes of Iraq and Syria and attracted thousands of foreign jihadists to its cause, including more than 500 Britons.
A new Counter-terrorism and Security Bill, containing a range of draconian powers including new orders that can block suspected British fighters from returning to the UK, is passing through Parliament.
Last May, father of two Mashudur Choudhury became the first person in the UK to be convicted of terrorist offences in connection with the Syria conflict.
The 31-year-old went to the Middle Eastern country with the intention of joining a terrorist training camp last October.