Taylor Swift terror plot linked to ISIS: Are they still a threat?

ISIS may have seen its power wane in recent years, but the infamous terrorist group is again generating global attention and alarm after it was connected to an alleged plot to attack Taylor Swift's concerts in Vienna.

An Austrian man arrested in connection with the plot pledged his allegiance to ISIS, authorities said on Thursday.

The 19-year-old man, who officials have not named, swore allegiance to the terrorist group online, Austrian general director for public security Franz Ruf said at a news conference.

He planned to use chemicals, machetes, and other devices stockpiled at his home in the planned attack, according to Ruf.

The plot also prompted the arrest of two other Austrian teenagers, ages 17 and 15, and the cancellation of three concerts in Vienna on Swift's Eras Tour.

The foiled plot is the latest to be linked to ISIS, a terrorist group also known as the Islamic State. ISIS primarily operates in northern and eastern Syria and northern Iraq, a region where it held significant amounts of land prior to 2019.

The group isn't the geo-political force it once was, but it has continued to be connected to terrorist attacks in several countries in recent years.

Authorities say ISIS-K, a notorious branch of the group, was behind the bombing that killed hundreds, including 13 American servicemembers, during the U.S. withdrawal from Afghanistan in 2021 and an attack on a Moscow concert hall that killed 140 people in March.

Here's what to know about the terrorist group.

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What is ISIS?

The group now known as ISIS first emerged by name in Syria during the civil war in 2013, although it has links to an offshoot of Al-Qaida formed in Iraq in 2004, according to the National Counterterrorism Center. A year later, it separated from Al-Qaida and laid claim to a wide swath of territory in both countries.

At its height, the group held around a third of Syria and 40% of Iraq, according to the Wilson Center.

Numerous terrorist attacks attributed to the group have killed thousands through the years. In one of the first large attacks linked to the group in Kobani, a northern Syrian city, as many as 262 civilians were killed and more than 270 were injured, a Human Rights Watch investigation concluded.

U.S. authorities have linked ISIS to multiple other attacks that have killed thousands in the years since, including a 2021 suicide bombing in Baghdad and a 2022 attack on a prison in Al-Hasakah, Syria, that killed more than 500 prison guards and detainees.

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Did ISIS go away?

Since 2019, ISIS' power waned after it incurred heavy damage from attacks carried out by the U.S. and other forces. That year, ISIS was expelled from its last stronghold in Syria, and ISIS-K was decimated by U.S. and Taliban attacks.

But several major terrorist attacks attributed to the group in the years since have put counterterrorism officials on the alert.

A Defense Department review pinned the 2021 bombing in Kabul amid the withdrawal of U.S. forces from Afghanistan on a "lone ISIS-K suicide bomber." The attack outside Hamid Karzai International Airport killed more than 170 Afghan civilians and 13 U.S. servicemembers.

ISIS claimed responsibility for an attack in March on the Crocus City concert hall in Moscow that saw four gunmen open fire on the crowd, killing at least 140 people.

What do officials say about ISIS-K?

ISIS-K, or ISIS-Khorasan, is one of the Islamic State's most brutal branches, according to the Counterterrorism Center. "The Khorasan" is an older name for an area of land including parts of Afghanistan, Iran, and Turkmenistan that the group seeks to control.

After its emergence in Afghanistan in 2014, the group became one of ISIS' most active regional affiliates. In Afghanistan, it targets the Taliban.

Military officials warn that the U.S. is "target No. 1 for ISIS-K," although the group currently lacks the capability to strike. “They clearly would like to strike the homeland, but their challenge is penetrating our security, which has proven to be quite resilient in recent years," according to retired Army general Mark Quantock, who oversaw U.S. Central Command's intelligence operations.

General Michael Kurilla, the commander of U.S. Central Command, told a senate committee in March of last year that ISIS-K would have the capability to "do an external operation against U.S. or Western interests abroad in under six months, with little to no warning."

Contributing: Rachel Smith and Thao Nguyen; Reuters

This article originally appeared on USA TODAY: Taylor Swift terror plot: Is ISIS still a threat?