U.S. officials confirmed Tuesday that Al Qaeda No. 2 Abu Yahya al-Libi was killed in a drone strike in Pakistan on Monday. According to the anonymous officials, Libi was crucial to the group’s planning operations and will be difficult to replace. The strike killed a total of 15 people, whom the U.S. government claimed were suspected militants. Pakistan has not confirmed the killing, but the strike sparked anger and a complaint to U.S. diplomats about ongoing drone strikes.