An Australian man who is editor of the whistleblower website WikiLeaks has told SBS he suspects the Pentagon is concealing a damning report into its troops' accidental killing of two journalists in Iraq in 2007.
Julian Assange says it is clear from the wording of the official report on the incident that a second probe was never released.
The official document does not discuss whether troops were within their rights to fire on the men because this was investigated in a 'collateral report', according to Assange, WikiLeaks' co-founder.
"If you look really closely, you see this is not actually the report that looked in to whether the soldiers had followed the rules of engagement," Assange told SBS.
"There's actually another one that they did not release ... because they say it is covered in a collateral investigation."
Suspected militant 'had one arm'
The Pentagon says US troops opened fire on a group walking down a Baghdad street because some of them were carrying AK47 rifles and rocket-propelled grenade launchers.
Assange says WikiLeaks initially agreed with that assessment based on video footage, but closer inspection revealed one of the men thought to be carrying an AK47 had one arm, which would make it impossible for him to use a semi-automatic rifle.
WikiLeaks posted the video of the killing yesterday. It was recorded in the Apache helicopter from which the troops attacked the group on the ground.
WikiLeaks made a request for the video under the Freedom of Information Act, but were knocked back for three years, Assange says.
Eventually they received the encrypted footage from whistleblowers within the military. The graphic footage shows several men being shot, and a van that comes to rescue them being attacked too.
Calls for probe
The Iraqi Journalists' Union has called on the government to probe the incident.
"This is another crime added to the crimes of the U.S. forces against Iraqi journalists and civilians," the head of the journalists' union Mouyyad al-Lami said. "I call upon the government to take a firm stance against the criminals who killed the journalists."
Meanwhile, the White House has described video as "tragic."
But President Barack Obama's spokesman Robert Gibbs stressed after the previously classified video was released by WikiLeaks that US forces in war zones take pains to avoid civilian casualties.
The gun camera footage, posted on the internet, includes audio conversations between Apache pilots and controllers in which they identify the men in a Baghdad street as armed insurgents and ask for permission to open fire.
Obama 'hasn't seen' the video
"I do not know whether the president has seen the video that was released on the internet. Obviously, it is very graphic in nature and it's extremely tragic," Gibbs told reporters on Tuesday.
"Our military will take every precaution necessary to ensure the safety and security of civilians, and particularly those that report in those dangerous places on behalf of news organisations."
Gibbs referred all questions about investigations into the July 2007 incident to the Pentagon.
WikiLeaks said that it had obtained the video "from a number of military whistleblowers" and decrypted it. It posted the video at collateralmurder.org.
The footage shows an aerial view of a number of men on a Baghdad street including two later identified as Reuters employees Namir Noor-Eldeen and Saeed Chmagh.
Camera mistaken for RPG
At least two individuals in the video appear to be carrying weapons but most are unarmed. The Apache pilots also appear to mistake a camera carried by one of the Reuters employees as a rocket-propelled grenade launcher or RPG.
At one point, the Apache pilots tell controllers they have spotted "five to six individuals with AK-47s" and ask for permission to "engage."
The Apache pilots open fire with the helicopter's cannon after which one says there are a "bunch of bodies lying there."
"Look at those dead bastards," one says. Another replies: "Nice."
Shortly after the initial shooting, a van pulls up to pick up the dead and wounded and is fired upon by the Apaches. Two children in the van were injured and evacuated by US ground troops who arrived later on the scene.
A US military official did not dispute the authenticity of the video but said it "doesn't give new information, it just gives footage."
"We had insurgents and reporters in an area where US forces were about to be ambushed," the official added. "At the time we weren't able to discern whether (the Reuters employees) were carrying cameras or weapons."
Investigation into WikiLeaks
Assange says he believes he and other WikiLeaks staff may have been under surveillance by the CIA or the US State Department.
An army spokesperson told AFP that WikiLeaks had been the subject of an investigation, after it published documents that may have threatened the safety of US troops in Afghanistan.
WikiLeaks said on Twitter last month that it believed a member of its staff had been followed by spies. Assange told SBS he had seen a man filming him at a cafe in Iceland, where he lives, but the man fled when approached.
Assange said the man had spoken to cafe staff in English, not Icelandic.