Abu Sayyaf (ASG) is a radical Sunni Islamist group that has aggressively attacked civilians since the 1990s. It is notorious for beheading both military and civilian captives, especially when kidnap-for-ransom demands are not met. ASG victims include Filipino citizens as well as foreign nationals. Abu Sayyaf primarily operates in western Mindanao and the Sulu Archipelago of the southern Philippines.