“Earlier this month, the top U.S. general in the Middle East said ISIS-K could attack U.S. and Western interests outside of Afghanistan “in as little as six months and with little to no warning.””
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While the attack by ISIS-K in Russia on Friday was a dramatic escalation, experts said the group has opposed Russian President Vladimir Putin in recent years.
“ISIS-K has been fixated on Russia for the past two years, frequently criticizing Putin in its propaganda,” said Colin Clarke of Soufan Center, a New York-based research group.
Michael Kugelman of the Washington-based Wilson Center said that ISIS-K “sees Russia as being complicit in activities that regularly oppress Muslims.”
He added that the group also counts as members a number of Central Asian militants with their own grievances against Moscow.”
https://www.yahoo.com/news/explainer-why-did-isis-k-011615857.html