Zachary Clark, 41, of Brooklyn, New York, pleaded guilty in Manhattan federal court, the U.S. Department of Justice said.
“Having pledged allegiance to ISIS, Clark provided specific instructions for how to conduct attacks in New York City, instructing others on knifing and bomb-making,” Assistant Attorney General for National Security John C. Demers said in a statement, using another acronym for IS.
According to criminal complaints filed in November 2019 in Manhattan federal court, Clark, also known as Umar Kabir, Umar Shishani and Abu Talha, pledged allegiance to IS’s then-leader Abu Bakr al-Baghdadi in July 2019.
Following Baghdadi’s death in a U.S. drone strike in October 2019, Clark pledged allegiance to his successor, Abu Ibrahim al-Sashemi al-Qurayshi.
Spreading IS propaganda
Since March 2019, Clark disseminated IS propaganda intended for members, associates, supporters and potential recruits of the terror group, according to court filings.
One way that Clark spread propaganda was to call on IS supporters to commit lone wolf attacks in New York City, the complaint said.
On Aug. 3, 2019, Clark reportedly posted instructions for conducting such attacks and how to avoid attracting the attention of law enforcement agencies.
He also posted a manual titled “Knife Attacks,” which said discomfort at “the thought of plunging a sharp object into another person’s flesh” is “never an excuse for abandoning jihad.”
Clark urged other participants in encrypted chat rooms to attack specific targets, posting maps and images of the New York subway system and encouraging IS supporters to attack those locations, the complaint said.
The court complaint also said that Clark’s guidance included posting a manual titled “Make a bomb in the kitchen of your Mom,” which was issued by al-Qaida in the Arabian Peninsula (AQAP) and included detailed instructions about constructing bombs using readily available materials.
Daryl Johnson, a former senior domestic terrorism analyst at the U.S. Department of Homeland Security, said many al-Qaida affiliates around the world have been producing online propaganda materials specifically designed to target Americans.
“They reach out to American audiences and plant ideas on how to conduct attacks without necessarily acquiring the materials,” Johnson told VOA, adding that “AQAP published Inspire Magazine, which was written and packaged for a Western audience, particularly Americans.”
Inspire is an English-language online publication that sought to spread al-Qaida’s extremist ideology. Anwar al-Awlaki, a U.S.-born al-Qaida propagandist who was killed in a U.S. drone attack in Yemen in 2011, was purportedly behind the magazine.
Last month, an American woman was arrested in the U.S. city of Phoenix in the southwestern state of Arizona before she could travel to join al-Qaida. She was reportedly radicalized through materials available online.
Law enforcement cooperation
Clark was arrested in Brooklyn and charged with one count of attempting to provide material support or resources to a designated foreign terrorist organization, namely IS, which carries a maximum sentence of 20 years in prison, according to the U.S. Justice Department. Clark is scheduled to be sentenced on Feb. 9, 2021.
His arrest was the result of cooperation between the FBI’s Joint Terrorism Task Force (JTTF) and other law enforcement agencies, U.S. officials said.
“Today’s plea by Mr. Clark is yet one more example of the resolve of the FBI’s JTTF in New York, and our many law enforcement partners, to protect this city and our citizens from the danger of lone wolf attacks,” FBI Assistant Director William F. Sweeney Jr., said in a statement on Monday.