The year 2011 presented a highly diverse terrorism picture in which the most notable trend was the increasing prominence of lone and solo actor plots, according to Europol, the law enforcement agency of the European Union.

"In 2011, the total number of terrorist attacks and terrorism-related arrests in the EU continued to decrease. This is a welcome development, but terrorism and violent extremism still represent a significant threat, and we must remain vigilant.," Europol director Rob Wainwright said.

"Sadly 77 people in Norway and another two in Germany were killed in 2011 by ‘lone actors’. Looking ahead, lone actors will continue to pose a threat, whether inspired by political or religious extremism. Organised underground groups also have the capability and intention to carry out attacks," Wainwright said.

Cecilia Malmström, European Commissioner responsible for Home Affairs, said that radicalisation into violent extremism and lone wolf attacks represents a significant threat for European citizens and have led to many tragedies, such as in Norway.

"We must reinforce our efforts to prevent violent extremism by becoming better at identifying individuals at risk of radicalisation," Malmström said.

"The Radicalisation Awareness Network launched by the European Commission last September is an important tool to help us in this work and I am looking forward to the presentation of its first results after the summer. The most important thing is to stand up against extremist views and propaganda across the spectrum, from online forums to the global political debate," she said.

The death of Osama Bin Laden has not removed the threat of al Qaeda-inspired terrorism. Instead, the threat has evolved and lone actors, or small EU-based groups, are becoming increasingly prominent, as is the Internet as a key facilitator for terrorism-related activities, Europol said.

The bomb attack and killing spree in Norway in July 2011, referred to in the TE-SAT report, and the arrests of individuals in a number of Member States for the preparation of terrorist attacks, are proof of the continuing need for vigilance.

The main figures for 2011 are:
·                                 174 terrorist attacks in EU member states.
·                                 484 individuals arrested in the EU for terrorist-related offences.
·                                 Lone actors were responsible for the killing of two people in Germany, and 77 people in non-EU country Norway.
·                                 316 individuals in concluded court proceedings for terrorism charges.
 
Terrorist and extremist groups have a substantial online presence, and the internet has become the principal means of communication for terrorist and violent extremist individuals and groups.

The internet is used for a range of purposes, including instruction, propaganda, recruitment, dispatch of members to conflict areas, fundraising, co-operation with other terrorist organisations, and the planning and coordination of attacks, Europol said.

Apart from its use as a communication tool, the internet offers new and additional possibilities to carry out electronic terrorist attacks, for example on the operating systems of critical infrastructure in EU member states, like energy production facilities and transport systems.

Leading members of al-Qaeda have already encouraged "electronic jihad" against critical infrastructure in Western countries, Europol said.

"Combating terrorism and violent extremism is a huge challenge which requires innovative measures and co-operation between many stakeholders," Wainwright said.

"Law enforcement authorities need to monitor suspicious activities, intelligence needs to be shared between agencies and information from the public needs to be considered. One fear is that the upcoming Olympic Games in London could be a target, which of course we must do our utmost to prevent," he said.