Iran's military defied new U.S. sanctions by reportedly holding a military exercise on Saturday. President Trump's administration imposed sanctions on individuals and entities linked to the Revolutionary Guards on Friday, following a recent Iranian ballistic missile test. Trump had warned Tehran of being put "on notice" for test firing the missile. Head of Revolutionary Guards' aerospace unit, Brigadier General Amir Ali Hajizadeh, said: "We are working day and night to protect Iran’s security." He added, "If we see smallest misstep from the enemies, our roaring missiles will fall on their heads." Still, Defense Secretary Jim Mattis said Saturday he was not planning to raise the number of U.S. forces in the area to address the country's "misbehavior."