A suicide bomber attacked an army bus in Kabul, killing four people and wounding 22 others on Sunday (January 26).<br/> <br />The casualties included army personnel.<br/> <br />Claimed by the Taliban, the attack is the latest in a surge of violence in the country.<br/> <br />The previous evening, an explosion hit northern Kabul, and security sources say a rocket struck an area near the airport.<br/> <br />Earlier this month - an attack on a restaurant popular with expats killed 20 people.<br/> <br />A U.S. general has said that such violence may have a chilling effect on aid groups and other foreign operations in Afghanistan, especially as the future of U.S. and NATO troops in the country remains uncertain.
