The Islamic State, a radical militant group terrorizing Iraq and Syria, also poses a threat to Russia, a Foreign Ministry official warned in comments published by Interfax on Monday, adding that from an ideological vantage point, the organization has an unlimited potential for expansion.
"At the moment, the threat to Russia is ideological, though it could be of a different character as well," Ilya Rogachyov, head of the Foreign Ministry's department on new and arising threats, told Interfax.
Fighters affiliated with the Islamic State could return home to Russia after having fought alongside the group in Syria, he said, a concern that has been repeated by Western and Russian leaders alike since the conflict in Syria began in 2011.
Chechen leader Ramzan Kadyrov warned of such an outcome in December, as did the Federal Security Service in September, when it estimated that about 400 Russians were fighting in Syria.
"Any terrorist threat of this scale is a threat for Russia because the consequences are very difficult to measure and predict," Rogachyov said.
"From an ideological standpoint, there are no limits to the Islamic State's expansion. And we're not talking only about the southern regions of Russia. They would be focused on all Muslim regions."
The Islamic State, which seeks to establish an Islamic caliphate and redraw the map of the Middle East, has claimed large swathes of territory in Iraq and Syria since April. Over the weekend, it moved closer to securing part of the Turkish border with Syria, The Guardian reported.
The Islamic State's rapid expansion has sent shockwaves through the international community, prompting the U.S. to launch air strikes in Iraq last week.
The militant group, which U.S. Defense Secretary Chuck Hagel described as "beyond anything that we've seen" and another top Pentagon official said displayed an "apocalyptic, end-of-days strategic vision," has also showed remarkable brutality.
Last week, members posted a video of the apparent beheading of a U.S. journalist who had gone missing in Syria two years ago.
Rogachyov described the group as a "remake" of al-Qaida, albeit one that had proved more successful in seizing territory. Al-Qaida has distanced itself from the Islamic State over the course of hostilities in Syria.
"Unlike al-Qaida, these bandits have seized substantial territories and set up their own administrations," Rogachyov told Interfax.
The group, which has developed a reputation for its social media savvy, has been known to post photos of "street cleaning" operations on Twitter in which members beautify the streets of seized territories, picking up litter and painting the curbs. These photos are often followed or preceded by photos of executions.