Six Canadian Nato soldiers and their Afghan translator have been killed by a bomb blast in southern Afghanistan, military officials have said.
This year has seen the heaviest fighting since 2001
The seven died when their vehicle struck a roadside bomb in the southern province of Kandahar.
The blast was the deadliest attack against Nato forces since six Canadian soldiers were killed on 8 April.
A total of 66 Canadian soldiers and a diplomat have died since the country sent troops to Afghanistan in 2002.
"Clearly, they have managed to kill six great young Canadians today, which is an absolute tragedy," said Canadian Brig Gen Tim Grant.
The bomb struck a vehicle travelling as part of a convoy south-west of the city of Kandahar.
British, Canadian and Dutch troops operate in the volatile southern province which was the birthplace of the Taleban and remains a stronghold for their forces.
The BBC's Charles Haviland, in central Afghanistan, says at least 30 Taleban fighters were killed in clashes with International Security Assistance Force (Isaf) troops earlier this week according to the city's governor, although Isaf has not confirmed the figures.
Correspondents say that fighting in recent months has been among the most violent since US-led troops overthrew the Taleban in 2001.
More than 100 foreign soldiers have died in Afghanistan so far this year, mainly in combat.