The FBI arrested a man on Saturday who pledged his alliance to ISIS and planned to attack churches in Idaho. Alexander Scott Mercurio, 18, was charged with attempting to provide material support or resources to a designated foreign terrorist organization, according to the Justice Department. The FBI’s Joint Terrorism Task Force conducted the investigation, CNN reported. Mercurio planned to attack churches in Coeur d’Alene, Idaho, on Sunday “using weapons, including knives, firearms, and fire,” according to court documents cited by the Justice Department. “Thanks to the investigative efforts of the FBI, the defendant was taken into custody before he could...