The US Army veteran was identified as 24-year-old Jack Danaher Molloy.

In a statement, US Department of Justice said: "Molloy was previously charged by criminal complaint with making false statements on Dec. 6, 2024, with much of the conduct underlying the charges in the indictment set forth in the complaint. Molloy was arrested in Chicago, Illinois, on Dec. 6, 2024, and transported by the U.S. Marshals Service to Pittsburgh on Dec. 30, 2024."

The US has designated Hezbollah as a 'terrorist' group.

"As alleged in the indictment and complaint, from in and around August 2024 through in and around December 2024, in Lebanon, Syria, the Western District of Pennsylvania, and elsewhere, Molloy attempted to provide material support and resources—namely, personnel (including himself) and services — to Hizballah, a foreign terrorist organization (FTO), knowing that the organization was a designated terrorist organization and that the organization had engaged in and was engaging in terrorist activity and terrorism.," read the statement issued by the department.

"As alleged, Molloy — a dual citizen of the United States and Ireland, who previously served on active-duty status in the U.S. Army — travelled to Lebanon in August 2024 and attempted to join Hizballah. While in Lebanon, Molloy was told by multiple individuals that the time was not right, and that he needed to take other steps before he could join the terrorist organization. Molloy then travelled from Lebanon to Syria in October 2024 in an effort to fight for Hizballah in Syria," the statement said.

After returning to the United States, Molloy resided in Upper St. Clair, where he continued his attempts to join Hizballah, including through communication with individuals online and in Lebanon, the department said.

During his time in the United States and abroad, Molloy also allegedly expressed his hatred toward and promoted violence against Jewish people.

If convicted, Molloy faces a maximum penalty of 20 years in prison for material support charge.

For false statement charges, he faces a maximum penalty of eight years in prison, a $250,000 fine, or both.