United States-led forces in Afghanistan say three of their soldiers have been killed in fighting with Taleban militants in north-eastern Afghanistan.
Two other soldiers were wounded in the clashes in Nuristan province - officials have not yet disclosed the nationality of those involved.
US-led troops on Friday raided a building in the south-east, killing three suspected al-Qaeda fighters.
Militants have been stepping up attacks on government and foreign forces.
"The soldiers killed and wounded today fought against extremists who oppose the rights of women, murder the innocent and harbour terrorists as they did during the Taleban regime," US Army Brig Gen James Terry said of Friday's fighting in Nuristan.
Nuristan has seen fierce clashes in recent days. US-led troops said they killed 15 insurgents on Wednesday who were trying to attack an army base.
US forces are pushing up to the northernmost points along the Afghan-Pakistan border in an attempt to crush militants, the Associated Press news agency reports.
Afghanistan has seen a surge in violence this year, particularly in the south where Taleban fighters have increased their attacks.
Three suspected al-Qaeda members were killed and three others detained in the eastern province of Khost during an operation by coalition forces, a US military statement said.
The raid was aimed at an al-Qaeda militant who was linked to a series of bombings, the statement said.
A suicide bombing on Friday in the southern province of Kandahar is now known to have killed a Canadian soldier serving with Nato-led forces. He was the seventh Canadian soldier to die in Afghanistan this month.
Nato's 8,000 soldiers took over control from US forces in the south on 31 July.
The soldiers, under the umbrella of Nato's International Security Assistance Force (Isaf), are in operating in the southern provinces of Helmand, Kandahar, Nimroz, Uruzgan and Zabul.