Islamic State-Khorasan (IS-K), the Islamic State offshoot that claimed responsibility for the August 26 suicide attack outside Kabul airport, has been behind some of the deadliest operations against Afghan civilians.
Its record includes a 2020 assault by gunmen on a maternity ward in Kabul, killing 16 mothers and pregnant women, as well as two children and seven other people.
The IS-K (also known as ISIS-K) has frequently targeted members of the Shi'ite Hazara minority, whom it views as heretics.
One Of The World's Deadliest Groups
IS-K was set up in 2015 and recruited heavily among Afghans and Pakistanis, particularly defectors from the fundamentalist Taliban.
It takes the "Khorasan" name from a historical region comprising parts of what are today Pakistan, Iran, Afghanistan, and Central Asia.
The group quickly established a reputation for ruthlessness and is believed to have also attracted members of other militant groups in the region, including the Islamic Movement of Uzbekistan (IMU).
The U.S. State Department designated it a "foreign terrorist organization" in January 2016, and within three years of its founding IS-K was among the world's four deadliest organizations on the Institute for Economics and Peace's Global Terrorism Index.
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IS-K has managed to survive a yearslong U.S. military campaign targeting it that apparently included the killing of a number of its leaders in U.S. air strikes. In 2017, the U.S. military dropped the so-called "mother of all bombs," the largest nonnuclear bomb in the American arsenal, on a cave complex in eastern Afghanistan used by IS-K.
IS-K was at one point believed to include up to 3,000 members, according to U.S. officials.
A United Nations report released in June said the group is thought to retain approximately 1,500 to 2,200 fighters in small areas of Afghanistan's Kunar and Nangarhar provinces. The UN authors assessed that it had been forced to decentralize into cells and small groups across the country, acting autonomously while sharing the same ideology.
U.S. officials and others have warned recently that the group could leverage instability in Afghanistan to consolidate its position there. Ahead of the deadly August 26 attack on Kabul airport, U.S. President Joe Biden and his national-security adviser, Jake Sullivan, warned that the threat from IS-K was "acute."
The group was said to have faced setbacks in past months, including territorial losses, but researchers tracking terrorist groups had previously been citing signs of an IS-K resurgence for over a year.
The UN warned in its report that, since June 2020, under an ambitious new leader named Shahab al-Muhajir, IS-K had remained "active and dangerous," and was seeking to swell its ranks with disaffected Taliban fighters and other militants.
"In July, it deployed 19 times as many attacks as it did in the same month last year," Charlie Winter, a senior research fellow at the International Center for the Study of Radicalization (ICSR), told RFE/RL. "It was able to do this because of a deteriorating security environment, changes in its leadership, and an expansion of its targeting parameters."
He said that the Taliban takeover of the Afghan capital marked a new, albeit brief, phase of IS-K activities leading up to the August 26 bombing: "When Kabul fell to the Taliban, [IS-K] ceased all activity so it could plan for this moment."
Abdul Sayed, an expert on jihadist groups in Afghanistan and Pakistan who is based in Lund, Sweden, said in a series of Tweets that IS-K had been taking "a new shape" since February 2020 and had become more dangerous.
"First, it announced and started planning a long new war against the Taliban, anticipating in light of [the] U.S.-Taliban deal that [the] Taliban will soon take power in Kabul with the U.S. withdrawal. I saw signs in Nangarhar & Kunar that it started gathering recruits for this new campaign," Sayed tweeted following the deadly attacks outside Kabul airport.
He added in a thread: "[IS-K's] emir Dr. Shahab al-Muhajir, appointed in May 2020, also announced a new urban terrorism campaign against the Taliban, the Afghan government, and 'their U.S. masters.'"
IS-K And The Taliban: Enemies
Researcher Winter speculated that the goal of the suicide attack outside Kabul airport that killed more than 100 people, including 13 U.S, troops, was to demonstrate that the Taliban cannot provide the security it has promised. It also sought to goad the United States into extending its presence in Afghanistan, he suggested.
"From a strategic perspective, they were as much aimed at the Taliban as they were the Afghan citizens and U.S. soldiers that were killed. As the Taliban tries to consolidate its position in Afghanistan, [IS-K] will do all it can to undermine it," Winter said.
He said such attacks "play into the hands" of both IS-K locally and Islamic State globally.
"They are not about 'establishing' Afghanistan as a new core of the caliphate -- at least, not yet," Winter said. "They are about demonstrating presence, defiance, and intent, and shaping the terrain for future insurgency."
The Taliban, which now controls most of Afghanistan after meeting with little military resistance as U.S.-led international forces accelerated their withdrawal from the country, has condemned the August 26 attack.
In an August 27 interview with RFE/RL's Radio Azadi, Taliban spokesman Zabiullah Mujahed appeared to downplay the threat from IS-K.
"The [IS] that existed in Iraq and Syria does not exist in Afghanistan," he said. "There are some people here who have taken the idea of [the Iraq and Syria IS] or call themselves their followers -- we are very confident that they will understand the reality when they see that an Islamic government has been established in Afghanistan, security is in place, and there are no foreign forces. So, there is no excuse for their insurgency and activity."
There are few indications of genuine security in Afghanistan, where numerous reports have emerged of revenge killings and the United Nations and rights groups have warned of likely war crimes and other atrocities as the Taliban captured territory, in the past month especially.
The U.S. president has vowed to retaliate against Islamic State and make it "pay" for the airport attacks. Speaking on August 26, Biden said U.S. commanders have been ordered to develop operational plans to strike IS-K assets, leadership, and facilities.
A former CIA director and defense secretary under the Obama administration, Leon Panetta, warned that Biden's pledge suggested that "we're going to have to go back in [to Afghanistan] to get [IS]."