When a van pulled up in what appeared to be an attempt to get the shooting victim to hospital, a second helicopter opened fire.

Victim: Reuters photographer Namir Noor-Eldeen, 22, died in the attack. He was covering a story about weightlifting at the time

Distraught: An Iraqi man weeps as he walks next to the vehicle carrying the coffin of Namir Noor-Eldeen

Later discovered two children in the van had been injured.

Reuters photographer Namir Noor-Eldeen, 22, was also killed.

The Reuters men were hit because their cameras were mistakenly identified as guns.

David Schlesinger, Reuters' editor in chief, said the deaths were 'tragic and emblematic of the extreme dangers that exist in covering war zones'.

Reuters has pressed the U.S. military for a full investigation.

Iraqis carry the coffin of Saeed Chmagh, an Iraqi driver working with Reuters, during his funeral in the holy Shiite city of Najaf in 2007

Shattered: An Iraqi man stands near the wreckage of a mini-bus at site where an Iraqi photographer and driver working for Reuters were killed