Al-Qaida's branch in Yemen is focusing on expanding its presence in a remote eastern province that is the ancestral homeland of Osama bin Laden, even as it remains the target of U.S. drone strikes and Yemeni military assaults, according to Yemeni officials.

Last year, a U.S.-backed Yemeni military offensive drove the militants from the southern province of Abyan, which the fighters had seized during the country's Arab Spring revolt and controlled for more than a year as they sought to create an Islamic emirate from which to attack the Yemeni government and Western targets. But in recent months, al-Qaida in the Arabian Peninsula, as the affiliate is known, has bolstered its presence in Hadramaut, the country's largest province, whose name some scholars say roughly translates as "Death is among us." The region abuts Saudi Arabia, a key U.S. ally.

"After the ousting of al-Qaida from Abyan and the fleeing of the armed militants to different areas, it seems that al-Qaida has shifted its attention toward Hadramaut," said Ali Alsarari, a political adviser to Yemen Prime Minister Mohammed Basindawa. "They control some areas and are trying to do what they did in Abyan."