WASHINGTON (Sputnik) — Authorities in European countries have also warned the public about possible attacks by lone individuals inspired by extremist organizations, the State Department noted.
"Credible information indicates terrorist groups such as ISIL [Daesh] and al-Qaeda and its affiliates continue to plot near-term attacks in Europe," the message warned on Thursday. "All European countries remain vulnerable to attacks from transnational terrorist organizations."
"Authorities believe there is a high likelihood terror attacks in Europe will continue as European members of ISIL [Daesh] return from Syria and Iraq," it added.
The Islamic State, also known as Daesh, has been designated as a terrorist group and is outlawed in the United States, Russia and numerous other countries. The terror group has seized large areas in Syria and Iraq where it declared a caliphate ruled by Sharia law.
A US-led coalition of more than 60 nations has been conducting airstrikes against Islamic State positions since August 2014.