BRUSSELS—The European Union’s police agency said Islamic State attackers have shifted focus to softer, more-random European targets in an effort to intimidate the public, instead of aiming at the police or military.

The militant group retains the will and capability to stage attacks in Europe in the near future, according to a report by Europol’s European Counter Terrorism Centre. While attackers will continue to use guns, bombs, knives and vehicles in Europe, they could also import terrorism techniques used in Syria and Iraq, such as car bombs, the report said.

The EU faces threats from both networked groups and lone-wolf attackers, and is prone to attacks that are carefully planned as well as those that appear spontaneous, according to the report. While Islamic State, also called ISIS or ISIL, is the main group threatening Europe, the report said al Qaeda and other jihadist groups remained a potential threat.

The Europol report said all EU member states were at risk of the types of attacks that have occurred recently in Franceand Belgium. The report, echoing past statements by European officials, said as Islamic State is weakened in Syria and Iraq there is the possibility that foreign fighters might try to enter the EU at a higher rate, posing “a significant and long-term security challenge.”

“We have to be vigilant, since the threat posed by the so-called Islamic State and returning foreign fighters is likely to persist in the coming years,” said Gilles de Kerchove, the EU counterterrorism coordinator. “These people are trained to use explosives and firearms and they have been indoctrinated by the jihadist ideology.”