Idaho teen arrested for making ISIS threats

(NBC, KYMA/KECY) - Authorities have arrested an Idaho teenager accused of planning to kill churchgoers in the name of ISIS.

18-year-old Alexander Mercurio of Coeur d'Alene was arrested early Saturday as part of an FBI Joint Terrorism Task Force investigation.

The arrest happening just a day before prosecutors say the teen planned to attack multiple local churches. The timing of which would coincide with the end of the Muslim holy month of Ramadan.

Investigators say Mercurio planned to use weapons, including knives, firearms as well as set fires.

He is now charged with attempting to support ISIS's mission of terror and violence and faces up to 20 years in federal prison if convicted. A court date has not been set.

NBC News could not immediately identify an attorney for Mercurio.