The deadliest attack was the bombing of a military convoy delivering books to a school in southern Afghanistan's Zabul province in which three service members, a State Department civilian and a Department of Defense civilian were killed, according to U.S. officials.

CNN: Afghan attacks kill 6 Americans as Dempsey arrives

The attack was the deadliest in Afghanistan since December 2011, when at least 70 people were killed in a blast at Kabul's Shia shrine.

BBC: Nato air strike in Ghazni 'kills Afghanistan police'

The attack in the north of Iraq was the deadliest single incident involving the US military in five months.

BBC: US troops killed in Iraq bombings

But German Defence Secretary Franz Josef Jung has defied calls to resign over the incident - the deadliest involving German troops since World War II - and a defence ministry spokesman insisted the decision to attack was "militarily necessary and correct".

BBC: Merkel regrets Afghan raid deaths