The Afghan Defense Ministry says its troops, along with NATO forces, have killed 17 rebels in the southern region of the country.
The ministry said Sunday the fighting erupted after militants fired several mortars at an Afghan army position in the province of Zabul.
Officials say one wounded rebel was captured.
On Saturday, NATO-led forces in Afghanistan said more than 25 international and Afghan National Security Force personnel were mistakenly killed or wounded during an operation in western Badghis province.
A NATO statement said Friday's incident occurred when NATO and Afghan forces were searching for two American soldiers who disappeared Wednesday while attempting to recover airdropped supplies from the Marghab River. The U.S. soldiers are believed to have drowned.
The statement says that in the course of the search operation the joint force was engaged by enemy forces and called for air support.
Four Afghan soldiers, three police and a civilian working with the Afghan army were killed, while five U.S. and 15 Afghan troops, along with two police and one civilian were wounded.
Afghan spokesman Zamary Bashary told VOA it is clear the incident was a mistake, adding it will not deter Afghanistan's partnership with international forces.
Some information for this report was provided by AFP, AP.