The Norwegian defense ministry confirmed the nationalities of the four killed by a roadside bomb in Afghanistan's north on June 27. A fifth ISAF service member was killed during an attack by insurgents in the south on the same day.

The Taliban-led insurgency in Afghanistan is growing stronger despite the presence of more than 150,000 foreign troops, with violence at its worst levels since the Islamists were ousted by US-backed forces in late 2001.

More than 90 foreign troops have been killed so far in June, the deadliest month for international forces since the war began. More than 310 have been killed so far this year, compared with about 520 deaths in all of 2009.

Another six ISAF troops were killed in separate incidents at the weekend.