Terrorism arrests rise sharply in year to June

It said the figure was the highest since records began in 2001 and included 12 arrests related to the Westminster attack in March this year, 23 to the Manchester Arena attack in May as well as 21 arrests in the wake of the London Bridge attack in June and one following the Finsbury Park attack which occurred soon after.

In its quarterly bulletin on police use of counter-terrorism powers, the Home Office said 123 of those arrested were charged, of which 105 were taken in on terrorism offences. Meanwhile, 189 were released without charge.

The remainder were bailed or faced alternative action of some kind.

Of the 105 charged, 32 have been prosecuted and found guilty while 68 are still to be prosecuted.

The number of terrorists in British prisons has also risen over the past year - by 35 per cent to 204.

The Home Office said that 91 per cent of those in jail were Islamic extremists while five per cent were far-right extremists.