WASHINGTON (Reuters) - A video showing U.S. Apache helicopters killing 12 people, including two Reuters news staff, is painful to watch but an investigation into the attack was very thorough, Defense Secretary Robert Gates said on Sunday.
"It's unfortunate. It's clearly not helpful. But by the same token, I think -- think it should not have any lasting consequences," Gates said of the 2007 videotape when interviewed on the ABC News "This Week" program.
The U.S. forces involved were in combat, he said, and were operating in "split-second situations."
The stark helicopter gunsight video of the July 12, 2007, attack has been widely viewed around the world on the Internet since its release on April 5 by the group Wikileaks, which promotes leaks to fight government and corporate corruption.
Some international law and human rights experts say the Apache helicopter crew in the footage may have acted illegally. The video includes an audio track of a helicopter crew conversation. Many have been shocked by the images and some of the fliers' comments.
"It's obviously a hard thing to see. It's painful to see, especially when you learn after the fact what was going on. But you -- you talked about the fog of war. These people were operating in split-second situations," Gates said.
The U.S. military said an investigation shortly after the incident found that U.S. forces were unaware of the presence of news staff and thought they were engaging armed insurgents, mistaking a camera for a rocket-propelled grenade launcher.
The Reuters staff killed in the attack were photographer Namir Noor-Eldeen, 22, and his assistant and driver Saeed Chamagh, 40.
"We've investigated it very thoroughly," Gates said on ABC. The military's Central Command said last week it had no plans to open a new investigation.
David Schlesinger, Reuters editor-in-chief, said: "I urge the secretary of defense to meet with me to help ensure a tragedy like this never happens again. We need to have transparency, accountability and an acknowledgment of the vital role journalists play in telling the story of war."
Asked by ABC whether the release of the video would damage America's image abroad, Gates said: "I don't think so."
"They're -- they're in a combat situation. The video doesn't show the broader picture of the -- of the firing that was going on at American troops."
Wikileaks said it obtained the video from military whistleblowers and posted it at http://www.collateralmurder.com.
Amnesty International called on Wednesday for an independent, thorough and impartial investigation into the incident shown in the video.
(Writing by Susan Cornwell, Editing by Howard Goller)