Half of the people arrested in Britain for suspected terrorism offences since the 11 September attacks in 2001 have been released without charge. Fewer than a fifth of the 572 people detained were charged with terrorism offences, with the rest facing criminal trials or being accused of breaking immigration laws.

The statistics were disclosed after police released the 10 suspects arrested during a high-profile anti-terrorist operation in Manchester and surrounding areas. The nine men and one woman were held on suspicion of the commission, preparation or instigation of acts of terrorism, which led to headlines wrongly suggesting they had plotted to set off a bomb in Manchester United's Old Trafford stadium.