Islamic State and other militants are able and likely to attempt fresh attacks in Europe following those in Paris in November, the EU's police agency Europol warned.
Director of Europol, Rob Wainwright, told a news conference that "the so-called Islamic State had developed a new combat style capability to carry out a campaign of large-scale terrorist attacks on a global stage - with a particular focus in Europe."
Unveiling the findings of a new Europol report on how the jihadist group operates, coinciding with the launch of the agency's new counter terrorism centre in The Hague, Wainwright added: "So-called Islamic State has a willingness and a capability to carry out further attacks in Europe, and of course all national authorities are working to prevent that from happening."
Europol's eight-page public report said further attacks could even take place quite soon.
The events in Paris "appear to indicate a shift towards a broader strategy of IS going global, of them specifically attacking France, but also the possibility of attacks against other member states of the EU in the near future," it said.
It warned there was "every reason to expect" an attack, by Islamic State or "IS-inspired terrorists or another religiously inspired terrorist group".
"This is in addition to the threat of lone actor attacks, which has not diminished," it added.
Some 30 Europol experts are currently working to support the Franco-Belgian investigation into the Paris attack, Wainwright said, helping track movements of money, weapons, fake documents and other elements of the plot.
IS had developed an "external action command" which was trained for "special forces-style attacks" internationally, the report said.
But it played down fears that jihadists were smuggling themselves into Europe as part of the huge wave of refugees and migrants that the continent is dealing with, many of whom are fleeing the war in Syria.
Wainwright welcomed what he called a "considerable improvement" in the level of intelligence information that EU governments were now willing to share with each other through Europol following the attacks on Paris.