Conviction of fertiliser plotters: statement by Jonathan Evans

Today five individuals were found guilty of terrorist-related offences after a trial at the Old Bailey.

I welcome this outcome. It is recognition of the hard work put in by my staff, the police and other agencies, and represents another plot prevented - one of a growing number of potentially devastating attacks the Security Service has stopped.

But the severity of the threat facing our country means expanding counter-terrorist operations at an unprecedented rate just to keep pace. We calculate the number of those with similarly violent intentions to those convicted today has increased substantially since 2005.

My Service has never been complacent. The attack on 7 July in London was a terrible event. The sense of disappointment, felt across the Service, at not being able to prevent the attack (despite our efforts to prevent all such atrocities) will always be with us. The reality is that whilst we will continue to do everything in our power to protect the UK public, we must be honest about what can and cannot be prevented in a democratic society that values its freedoms.

We are today on our website providing more information to the public on the links between those convicted today and the 7 July bombers. The Security Service will never have the capacity to investigate everyone who appears on the periphery of every operation. I believe the account we are publishing here will make this clear.