As many as three Afghan civilians were killed early on Monday morning when American troops opened fire after their vehicle struck a roadside bomb, an official in eastern Nangarhar province said.
Three American troops were wounded Sunday when an Afghan soldier opened fire in southern Helmand province, officials said, in the first known "insider attack" on international forces this year.
Filipino and US troops began training exercises this week, the Philippines military said on Wednesday, despite President Rodrigo Duterte's threats to end joint war games and kick American soldiers out of his country.
Philippine President Rodrigo Duterte said Wednesday he wants US troops out of his country in the next two years and is willing to scrap defence pacts with longtime ally Washington if necessary.
The United States is sending about 600 extra troops to Iraq to train local forces for an upcoming offensive on the Islamic State group stronghold of Mosul, Defense Secretary Ashton Carter said on Wednesday.
President Barack Obama, saying the security situation in Afghanistan remained precarious, said he will keep US troop levels there at 8,400 through the end of his administration rather than reducing them to 5,500 by year's end.
Hundreds more US troops are headed for Afghanistan's strife-torn Helmand province to shore up security forces who have struggled in the face of sustained Taliban attacks, officials said.