(VOVworld) -  The European Police Office (Europol) warned on Wednesday that the EU is facing major risk of so-called "lone-wolf" terror attacks, after series of bloody attacks that killed hundreds of people.

French police secure the area as the investigation continues at the scene near the heavy truck that ran into a crowd at high speed killing scores in Nice, France. (Photo: Reuters)

The world was shocked last week by an axe rampage on a German train in Wuerzburg and a truck attack in Nice, France, which Europol said, were similar to attacks carried out by IS and al-Queda. Although IS claimed responsibility for the recent attacks, they don’t seem to have been planned, logistically supported, or executed by IS members. Direct IS involvement cannot be established, Europol said.