Hundreds of young Afghans gathered in the streets of eastern Afghanistan have demanded an end to foreign occupation in protests against the shootings of 16 civilians in their homes by a rogue military officer.
The Pentagon has not yet released the name of the soldier who allegedly shot dead nine Afghan children, three women and four men in two Kandahar province villages.
Student shouted slogans such as "Death to America" and "Death to the soldier who killed our civilians!" in Jalalabad city, 80 mile east of Kabul.
Some carried a banner that called for a public trial of the soldier. Other protesters burned an effigy of Barack Obama.
At a memorial service for the dead civilians Taliban militants opened fire on senior Afghan government officials. Among those at the service were two brothers of Afghan president Hamid Karzai and the army's chief of staff.
"Everyone was in the mosque when it happened, and suddenly the police and other security people went to return fire," Abdul Rahim Ayoubi, the MP for Kandahar, who was part of the group, told the Guardian.
"All our delegation is okay - they were shooting from a long way away," he added.
Four members of the security forces were injured in the attack, but no one was killed, according to reports.
Prime Minister David Cameron is expected to meet Barack Obama to discuss the timetable for withdrawal of troops from Afghanistan.
Obama has already warned against "a rush for the exits" in the country.
"It's important for us to make sure that we get out in responsible way, so that we don't end up having to go back in," Obama said. "But what we don't want to do is to do it in a way that is just a rush for the exits."
The war in Afghanistan is now in its 11th year. The rogue killing has sparked further distrust between Washington and Kabul, whose diplomatic relations are stretched to breaking point after the burning of the Koran by American soldiers in February and an earlier video showing American marines urinating on dead Taliban suspects.