(CNN) - Abu Yahya al-Libi, al Qaeda's No. 2 man, was killed in Pakistan on Monday, according to U.S. officials.
Al-Libi's death was "another serious blow to core al Qaeda," White House spokesman Jay Carney said.
Al-Libi, 49, was a well-regarded figure in jihadist circles and had emerged as one of the terrorist network's most important clerics and propagandists, appearing in countless videos in recent years.
He was killed by a CIA drone strike, according to U.S. officials. Drone strikes remain a highly contentious issue between the United States and Pakistan.