At least 57 people were killed on Monday in Yemen when fighters from an al Qaeda-linked group attacked a military camp near the southern city of Lawdar, residents and local officials said.

The fighting started at dawn when militants from Ansar al-Sharia (Partisans of Islamic Law) attacked the camp in Abyan province, about 120 km from southern port city Aden.

The group seized control of a significant amount of territory in Abyan during the turmoil that led to the replacement of President Ali Abdullah Saleh by his deputy, a deal that Saudi Arabia and the United States hope will prevent al Qaeda from getting a foothold near key oil shipping routes.

Conflict with Islamists in the south is only one of several challenges facing new president, Abd-Rabbu Mansour Hadi, who took office vowing to fight al Qaeda, only to have more than 100 soldiers killed in attacks during his first few days in power.