Following are some of the deadly attacks in Western Europe in recent years:
Aug 17, 2017 - A van ploughs into crowds in the heart of Barcelona, killing at least 13 people, a regional official says, in what police say they are treating as a terrorist attack.
June 3, 2017 - Three attackers ram a van into pedestrians on London Bridge then stab revellers in nearby bars, killing eight people and injuring at least 48. Islamic State says its militants are responsible.
May 22, 2017 - A suicide bomber kills 22 children and adults and wounds 59 at a packed