Ten people were killed in southwestern Yemen on Sunday due to clashes between al-Qaeda militans and Yemeni tribe members. The shoot-out took place in the southwestern city of Marib, which is located in the east of capital Sanaa. Ten people including four al-Qaeda militans died in the clashes, according to local sources. Yemen has a long history of extremism and regional instability. The Yemeni-based al-Qaeda in the Arabian Peninsula is seen as one of the network\'s most aggressive branches, and a direct threat to the United States. Source: AA