Der Spiegel photos

NATO officials in Afghanistan said they are on alert after a German news magazine uncovered images of U.S. soldiers posing with dead Afghan civilians.

German news magazine Der Spiegel said it found roughly 4,000 photographs and videos showing U.S. soldiers posing next to the bodies of civilians killed during coalition strikes.

Officials with NATO's International Security Assistance Force in Kabul said the pictures could spark a reaction similar to the international uproar that followed the publication of pictures showing abuses at Iraq's Abu Ghraib prison, The Guardian newspaper in London reports.

There are 12 soldiers on trial for their alleged role in the deaths of three Afghan civilians. Five of them are on trial for murder after allegedly making the victims look like they were killed during a Taliban attack.

The United Nations and other international groups ordered their foreign staff on "lockdown" in the wake of the Der Spiegel publication.

U.S. security contractor DynCorp in a letter to its clients warned the Der Spiegel article could "incite the local population" because the "as the "severity of the incidents to be revealed are graphic and extreme," The Guardian adds.

The U.S. military in a statement apologized for the photographs describing them as "contrary to the standards and values of the United States."

The photos are among hundreds of pictures the U.S. Army has tried to block from publication as it tries five members of the 5th Stryker Brigade, 2nd Infantry Division, for the deaths of three unarmed Afghan civilians last year.