What is ISIS-K and why has it attacked Russia?

The four gunmen who carried out the attack have reportedly been arrested

In the weeks leading up to the tragedy at a Moscow music venue on Friday night, warnings had been relayed to Russia that a terror attack perpetrated by extremists was imminent.

Despite this, it appears their intelligence services were caught unaware when a group of four gunmen opened fire at Crocus City Hall, where 7,000 concertgoers had gathered to watch the progressive rock band Picnic.

At least 137 people have been killed, while over a hundred more have been wounded with the jihadist group ISIS-K claiming responsibility in a series of videos and messages.

The car which, according to Russian authorities, the suspects in the shooting at Moscow's Crocus City Hall used to escape (Ostorozhno Novosti via REUTERS)

The four suspects have since been arrested and hauled before a court, just hours after footage emerged of them being dragged into an intelligence headquarters whilst blindfolded.

Who are ISIS-K?

Islamic State Khorasan (ISIS-K), named after an old term for the region that included parts of Iran, Turkmenistan and Afghanistan, emerged in eastern Afghanistan in late 2014 and quickly established a reputation for extreme brutality.

While the group has seen a decline in membership since 2018, it remains one of the most active regional affiliates of Islamic State. Over the years, it has been increasingly targeted by US forces and the Taliban, both of whom have inflicted heavy losses upon the group.

Despite this, the US continues to view the group as a threat, with Congress told last March that ISIS-K was developing the ability to carry out “external operations” in Europe and Asia.

General Michael Kurilla, the commander of US Central Command predicted it would be able to attack U.S. and Western interests outside Afghanistan "in as little as six months and with little to no warning."

Why attack Russia?

Jihadist terror groups have often posed a challenge to Russia’s security, with ISIS-K previously carrying out the 2017 St Petersburg metro bombing in 2017, which left 15 dead.

The gunment opening fire in the concert hall foyer (UGC/AFP via Getty Images)

Largely based in central Asia, ISIS-K has come to view Russia on a similar level to the US, which they believe espouses “hatred” towards the Muslim faith.

They have also cited Russia’s support of the Assad regime which saw them intervene in Syria in 2015, with airstrikes occurring as recently as last year.

Michael Kugelman of the Washington-based Wilson Center said 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.

What other attacks have the group carried out?

Earlier this year, the US intercepted communications confirming the group carried out twin bombings in Iran that killed nearly 100 people who had gathered to mourn the anniversary of Iranian military officer Qasem Soleimani’s assassination by US forces.

In September 2022, ISIS-K militants claimed responsibility for a deadly suicide bombing at the Russian embassy in Kabul.

The group was also responsible for an attack on Kabul’s international airport in 2021 that killed 13 US troops and at least 169 civilians during the chaotic US evacuation from the country.