Kabul , Afghanistan ( CNN ) -- Two suicide bombers struck a joint U.S.-Afghan military base in central Afghanistan early Saturday , killing 13 people , authorities said . Among the dead were a child , two women and four policemen , said Shahidullah Shahid , a spokesman for the Wardak province governor . The attack wounded 78 others . One bomber attacked the base on foot , then another one detonated a truck , Shahid said . No international coalition service members died in the attack in Wardak 's Sayedabad district , according to Maj. Adam Wojack , a spokesman for NATO 's International Security Assistance Force . However two coalition members were wounded , Shahid said . The Taliban claimed responsibility for the attack . Violence against Afghan civilians fell in the first half of the year , according to a recent United Nations report . But even though attacks were down compared with the first six months of 2011 , violence is taking a `` devastating toll on civilians , '' the report said . In the first six months of this year , 1,145 Afghans were killed and 1,954 , injured -- down from the 1,510 killed and 2,144 injured in the same period a year earlier . The drop marked the first time in five years there has been a fall in violence against civilians , the report said . About 80 % of the attacks against civilians are by anti-government forces such as the Taliban , the report said . Journalist Abdul Qadir Sediqi contributed to this report .
NEW : 78 others are wounded . The attack comes as the United States is trying to build a coalition against Islamic State militants in Iraq and Syria. No international coalition service members are killed . The Taliban claims responsibility .