The five U.N. peacekeepers were from India and were part of a convoy of 32 Indian peacekeepers that came under attack in an ambush in Jonglei, South Sudan, according to Syed Akbaruddin, spokesman for India's Ministry of External Affairs.

CNN: UN: 5 peacekeepers, 7 others killed in South Sudan attack

Blackwater said its guards were protecting a U.S. diplomatic convoy when they came under fire in Nusoor Square in western Baghdad.

CNN: Blackwater defends team in Baghdad shootings

The Iraqis then organized a convoy to transport the 64 Syrians to another border crossing that remains under Syrian government control hundreds of miles to the south.

WSJ: Islamists Try to Firm Grip on Syria Regions

Earlier this week UN police came under attack in the town of Strpce after a Serbian man died while travelling in a UN convoy.

BBC: Serbs die in Kosovo bus blast

On Wednesday, Jordan sent a convoy of trucks across the Jordan River packed with relief aid for Palestinians under Israeli curfew in the West Bank.

BBC: Al-Qaeda 'opens new front in Jordan'

The pilots were under both time pressure and geographical pressure, as the convoy appeared to be heading towards a village, where the pilots could not strafe them, Mr Carroll said.

BBC: Does 'fog of war' excuse 'friendly fire?'