What We Know About ISIS-K, the Group That Claimed Responsibility for the Moscow Attack

The group that claimed credit for the deadly terrorist attack in Moscow on Friday is the Islamic State affiliate in Afghanistan called Islamic State Khorasan Province, or ISIS-K.

ISIS-K was founded in 2015 by disaffected members of the Pakistani Taliban, who then embraced a more violent version of Islam. The group saw its ranks cut roughly in half, to about 1,500 to 2,000 fighters, by 2021 from a combination of American airstrikes and Afghan commando raids that killed many of its leaders.

The group got a dramatic second wind soon after the Taliban toppled the Afghan government that year. During the U.S. military withdrawal from the country, ISIS-K carried out a suicide bombing at the international airport in Kabul in August 2021 that killed 13 U.S. troops and as many as 170 civilians.

The attack raised ISIS-K’s international profile, positioning it as a major threat to the Taliban’s ability to govern.

Since then, the Taliban have been fighting pitched battles against ISIS-K in Afghanistan. So far, the Taliban’s security services have prevented the group from seizing territory or recruiting large numbers of former Taliban fighters bored in peacetime — among the worst-case scenarios laid out after Afghanistan’s Western-backed government collapsed.

President Biden and his top commanders have said the United States would carry out “over-the-horizon” strikes from a base in the Persian Gulf against ISIS and Qaeda insurgents who threaten the United States and its interests overseas.