In the hours following the U.K.'s historic vote to leave the European Union, the Islamic State has reportedly called for attacks in Brussels and Berlin in order to "paralyze" Europe.
Britons voted Thursday my a margin of 52 percent to 48 percent to leave the EU, leading the Islamic State to celebrate the immediate negative economic effects of the monumental decision. The terror group's message reportedly came through the jihadi Telegram, an encrypted communication service often employed by Islamic State members and backers.
People gather to leave tributes at the Place de la Bourse following today's attacks on March 22, 2016 in Brussels, Belgium. At least 31 people are thought to have been killed after Brussels airport and a Metro station were targeted by explosions. The attacks come just days after a key suspect in the Paris attacks, Salah Abdeslam, was captured in Brussels. (Photo by Carl Court/Getty Images)
And the U.K. is taking the threats seriously. British military chiefs are warning there is a "serious and direct threat to holiday resorts across Europe" from terror groups like the Islamic State.
"There is considered to be a heightened threat of terrorist attack globally against U.K. interests and British nationals from groups or individuals motivated by the conflict in Iraq and Syria," the U.K.'s Foreign Office told the Daily Mirror.
Immigration was one of the key issues that led British voters to ultimately side with the "Leave" camp. A key principle of the EU is porous borders, allowing some 400 million people to move unreservedly throughout the 28-nation union.
That policy was the subject of intense criticism following the deadly terror attacks in Brussels and Paris as well as a thwarted attack last summer on a Paris-bound train.
Salah Abdeslam, the terror ringleader in Europe, was able to move freely from Brussels to Paris and, eventually, back to Brussels, where he hid out for four months. Investigators believe it was the same group that executed both attacks.
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