U.S. airstrikes in Yemen late last year killed key leaders of Al Qaeda in the Arabian Peninsula (AQAP), United States Central Command said in a news release Wednesday.

CENTCOM said Habib al-Sana’ani — an AQAP deputy arms facilitator said to be responsible for the movement of explosives, finances and weapons into parts of Yemen — died in an airstrike on December 19. It also said external operations facilitator Miqdad al Sana’ani died December 15, and that Abu Umar al-Sana’ani, a Dawah committee member within the organization, was killed November 20 in an airstrike.

U.S. forces are continuing counterterrorism operations in Yemen against both AQAP and the Islamic State of Iraq and Syria (ISIS) “to degrade these groups’ ability to hold territory and coordinate external attacks,” CENTCOM said.

AQAP formed nearly a decade ago, in 2009, and later grew into one of al Qaeda’s most dangerous affiliates, according to the Council on Foreign Relations. The organization gained strength amid unrest in Yemen, which has been ravaged by war between Houthis — Iran-backed Shiite rebels — and the internationally recognized government that is allied with a military coalition led by Saudi Arabia.

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