What to know about Islamic State group, which claimed the Moscow attack

It has been almost a decade since the Islamic State group, a former al-Qaeda affiliate, declared the establishment of a caliphate over swaths of territory in Syria and Iraq. The jihadist group, also known as ISIS or ISIL, called on all Muslims to join its caliphate and justified its attacks on other Muslims by accusing them of apostasy.

At the peak of its power, the group controlled an area the size of Britain, and systematically killed or enslaved members of the Yazidi religious minority, carried out torture and mass killings, and filmed gruesome videos of the executions of its captives, including Westerners. Militants in other regions also pledged allegiance to the group and formed local offshoots.

The extremist group also claimed responsibility for large-scale attacks in Europe and elsewhere, including attacks in Paris in November 2015 that claimed at least 130 lives and suicide bombings in Sri Lanka in 2019 that killed at least 359 people.

The Islamic State later lost control of its territory in Syria and Iraq, but militants have continued to carry out attacks there and abroad.

The extremist group claimed responsibility for the attack, according to its news agency Amaq. A U.S. official who spoke on the condition of anonymity to discuss sensitive information said the United States had “no reason to doubt” the group’s claim. Independent terrorism experts also said the characteristics of the raid appeared consistent with an Islamic State attack.

On March 7, the U.S. Embassy in Russia said that it was “monitoring reports that extremists have imminent plans to target large gatherings in Moscow, to include concerts,” and it urged U.S. citizens to avoid large gatherings. The U.S. government said it had also shared the information with Russian officials.

While the Islamic State has not said which of its branches was involved in the attack, two U.S. officials said that recent intelligence reporting indicated the Islamic State’s Afghanistan and Pakistan branch, known as Islamic State-Khorasan or ISIS-K, was active inside Russia.

Earlier this month, Russia’s Federal Security Service said it had foiled an ISIS-K attack on a Moscow synagogue, the country’s Tass news agency reported.

According to a 2017 report from the Soufan Center, which studies violent extremism, more foreign fighters joined Islamic State from the former Soviet republics than any other region. In 2015, militants in Russian provinces and republics pledged allegiance to the group and formed IS-Caucasus Province.

Islamic State has carried out other major attacks on Russian interests abroad: In 2015, a Russian plane carrying 224 people exploded over Egypt’s Sinai peninsula, killing all onboard; a local Islamic State offshoot claimed responsibility for the attack.

Eight people were also killed in an ISIS-K attack on the Russian embassy in 2021.

Russia’s heavy-handed rule over the Muslim majority North Caucasus region and its support for Syrian President Bashar al-Assad during the long-running civil war have spurred jihadist narratives against Russia and its President Vladimir Putin.

At the peak of its power, territory the group controlled in Syria and Iraq was around the size of Britain. But by early 2019, following airstrikes from a U.S.-led coalition and an assault by a Kurdish-led fighters against the group’s remnants in eastern Syria, U.S.-backed forces declared the final defeat of ISIS’s self-proclaimed caliphate. Later the same year, the group’s leader, Abu Bakr al-Baghdadi, died during a U.S. military operation in Syria.

But while the world’s attention has moved on, the group and its offshoots in the Middle East and elsewhere have continued to stage attacks, including a 10-day attack on a prison in Syria in 2022.

By August 2020, more than 10,000 Islamic State fighters were estimated to still be active in Iraq and Syria, U.N. counterterrorism chief Vladimir Voronkov said at the time.

In addition to its original heartlands in the Middle East, Islamic State also has branches in Asia and Africa.

Last year’s U.S. intelligence leaks on the Discord messaging platform revealed that Afghanistan in particular had become an important staging ground for planned Islamic State attacks across Europe and Asia, while a report from a U.N. Security Council committee last summer said that member states were growing increasingly concerned about ISIS-K’s ability “to project a threat into the region, and further afield into Europe.”

ISIS-K has carried out a number of large-scale attacks — some also preceded by U.S. warning of imminent attacks, including a deadly attack on Kabul airport during the international withdrawal from Afghanistan in August 2021. Dozens were killed, including 13 U.S. service members. Hours before the attack, U.S. and Western governments warned people to stay away from the airport amid a specific threat from ISIS-K.

Earlier this year, at least 95 people were killed in bombing attacks in Iran claimed by Islamic State.

Inside Afghanistan, the number of attacks have decreased in recent years, however, according to a report from the Washington Institute for Near East Policy published in September.