Al-Shabab overran an African Union base in southern Somalia early Tuesday, a Somali military official said, in the latest display of the extremists' capacity to hit back amid a prolonged offensive against them. The attack in the small farming town of Janale started with a suicide car bombing at the base's gate, followed by a firefight which lasted more than an hour. The African Union force in Somalia insisted on Twitter that it is still in control of the base. Yet, Al-Shabab said it killed about 50 AU troops from Uganda at the base.