The death toll has surged from weekend violence in Afghanistan , with six Americans and more than a dozen Afghan civilians reportedly among the casualties . Five Americans -- including a U.S. diplomat , a civilian from the Defense Department and three U.S. service members -- were killed while delivering books to an Afghan school , when a suicide bomber struck their convoy in southern Afghanistan 's Zabul province Saturday . Another U.S. service member was killed in a separate attack Saturday . The diplomat 's death was a grim reminder of the risks and importance of pushing for change in `` one of the toughest places on earth , '' U.S. Secretary of State John Kerry said . Anne Smedinghoff , 25 , is believed to be the first U.S. diplomat killed since a September attack in Benghazi , Libya . `` I think there are no words for anybody to describe the extraordinarily harsh contradiction of a young 25-year-old woman with all of the future ahead of her , believing in the possibilities of diplomacy , of changing people 's lives , of making a difference , having an impact , who was taking knowledge in books to deliver them to a school , '' Kerry said . In separate clashes in Kunar province on Saturday , local officials said , at least 11 children were killed in a NATO operation aimed at Taliban targets . NATO officials said they were investigating reports of civilian casualties . Kerry laments death of U.S. civilian in Afghanistan . Family : Diplomat `` was doing what she loved '' Kerry was emotional Sunday as he spoke to U.S. diplomats stationed in Istanbul about Smedinghoff 's death . Smedinghoff was `` vivacious , smart , capable , chosen often by the ambassador there to be the lead person because of her capabilities , '' Kerry said . The attack killed Afghan civilians and wounded four more State Department personnel . One of them was in critical condition in a hospital in Kandahar , Kerry told reporters Sunday . `` I wish everyone in our country could see first-hand the devotion , loyalty and amazingly hard and hazardous work our diplomats do on the front lines in the world 's most dangerous places , '' Kerry said in a statement Saturday . `` Every day , we honor their courage and are grateful for their sacrifices , and today we do so with great sadness . '' Smedinghoff volunteered for an assignment at the U.S. Embassy in Kabul and had been working there since July , her parents said in a statement . `` She particularly enjoyed the opportunity to work directly with the Afghan people and was always looking for opportunities to reach out and help to make a difference in the lives of those living in a country ravaged by war , '' Tom and Mary Beth Smedinghoff said . `` We are consoled knowing that she was doing what she loved , and that she was serving her country by helping to make a positive difference in the world . '' Afghan children killed . At least 11 Afghan children were killed Saturday in a joint military operation by Afghan and NATO forces , local officials said . Mohammed Zaher Sapai , governor of the Shigal district , said 11 children were among 18 people killed in the operation . NATO 's International Security Assistance Force is investigating , spokesman John Manley said . `` We take these reports of civilian injuries very seriously , '' he said . U.S. military brass visits . The chairman of the U.S. Joint Chiefs of Staff , Gen. Martin Dempsey , is in Afghanistan for meetings with coalition and Afghan leaders . Dempsey will be briefed on the ongoing military transition , where Afghan security forces are taking greater control of their country . He will meet with Marine Corps Gen. Joseph F. Dunford , who took command of ISAF about two months ago . `` One of the things I 'm going to ask ( Dunford ) is ... what have you learned , '' Dempsey told the American Forces Press Service . `` If he tells me 'Nothing , ' I 'm going to say , 'Maybe we got the wrong guy . ' '' Dempsey spokesman Col. David Lapan later told CNN that the chairman was simply joking when he made the remark about Dunford . Dempsey has total confidence in Dunford , Lapan said .
David Lapan `` was doing what she loved , '' her parents say . The 25-year-old is believed to be the first Kunar province diplomat killed since Benghazi . At least 11 civilians and 3 U.S. service members were killed delivering books to a school . Two children killed in an Afghan /NATO operation Saturday , officials say .