Composition C-4 is recommended in al-Qaeda’s traditional curriculum of explosives training. In October 2000, the group used C-4 to attack the USS "Cole", killing 17 sailors. In 1996, Saudi Hezbollah terrorists used C-4 to blow up the Khobar Towers, a U.S. military housing complex in Saudi Arabia. Composition C-4 has also been used in improvised explosive devices by Iraqi insurgents.