The European Union recorded more than 200 successful and failed terrorist attacks last year, the head of its counterterrorism centre said Monday.
The bloc has been hit by a number of terrorist attacks in recent years, most recently in Belgium on March 22, when more than 30 people were killed in suicide bombings at its main international airport and an underground railway station in the capital Brussels.
In 2015, a total of 151 people were killed and more than 360 injured during terrorist attacks in the EU, according to Manuel Navarrete Paniagua, the head of the European Counterterrorism Centre, which is part of the EU police agency Europol.
He provided EU parliamentarians on Monday with figures from an annual report on terrorism trends that Europol will release in the coming weeks. Its data is compiled from EU member states.
They reported 211 failed, foiled and completed terrorist attacks in 2015, Navarrete Paniague said. More than 1,000 people were arrested for terrorist-related offences.
The most deadly cases were due to what was classified as jihadist terrorism, with 17 attacks, 150 deaths and 667 arrests attributed to that phenomenon in 2015.
"Terrorist cells [that] are ready to perpetrate a terrorist attack in the EU are mostly domestic and locally based, but we are aware of the connection they have with the so-called Islamic State," Navarrete Paniague said.
Both lone attackers and foreign fighters - Europeans who travel to Syria or Iraq to fight alongside extremist groups such as the Islamic State - pose a "serious threat," he added.
"Having these conflict zones ... in Syria, Iraq and Libya providing some training and providing also the capability to obtain the means to perpetrate attacks, they really make them more dangerous," he said, noting however that there are also suspicions of training being carried out in other regions such as the Western Balkans.
Europol also tracks other terrorist groups.
Nationalists and separatists accounted for 168 arrests in 2015, while left-wing and anarchist attacks were at their lowest level since 2006, with 67 individuals arrested in six EU member states. One person was killed in a left-wing attack in 2015 in Greece.
Far-right extremists, meanwhile, stepped up their activities in 2015, building on increased "anti-immigration and anti-Islam sentiment," Navarrete Paniague said. Nine attacks were reported, compared to none the year before. Arrests decreased, however, from 34 to 11.
In general, the latest terrorist attacks in the EU "suggest a much better coordination by the terrorists" than previously recorded, Navarrete Paniague warned.