CHICAGO — A member of the Army National Guard and his cousin, both U.S. citizens, were arrested in Illinois for allegedly “conspiring to provide material support” to the Islamic State group, according to the Justice Department.

Spc. Hasan Edmonds, 22, was arrested at Chicago Midway Airport. He was attempting to fly to Cairo, Egypt. Jonas Edmonds, 29, was arrested at his home in Aurora, IL.

Hasan Edmonds planned to use his military background to fight with the Islamic State group. After his cousin’s departure, Jonas Edmonds was to carry out a planned attack against a military facility in the U.S.

On Wednesday, the Justice Department filed a criminal complaint in the U.S. District Court of the Northern District of Illinois. The two will appear before a judge at 4 p.m. ET. They face up to 15 years in prison and a $250,000 fine.

In late 2014, the FBI took notice of the cousins and opened an investigation. Both met with an undercover agent and detailed their plan to attack the facility where Hasan Edmonds was training.

In January, a U.S. Air Force veteran tried to join the Islamic State group in Syria, but was stopped by Turkish officials at the border. Tairod Nathan Webster Pugh was indicted earlier in March on charges of trying to give material support to a terror group and obstruction of justice.