An Al Qaeda-umbrella group claimed its militants killed three American soldiers after capturing them last month in Iraq, according to a new video released Monday.

"The Americans sent 4,000 soldiers looking for them and ... fearing that this will have bad repercussions, the state of Islam decided to and announced their killing making it a bitter result for the enemies of God because they were alive and then dead," said an unidentified voice on the video, which was made available to The Associated Press by the Washington-based SITE Institute.

The video does not offer any proof that the soldiers were killed and does not show the soldiers. The militants said in the video that the soldiers were buried, but again, did not offer proof. The unidentified voice blamed their deaths on: "The American army and their leaders, who do not care for the feelings of the soldiers' families."

The three U.S. soldiers were captured south of Baghdad on May 12 in an ambush later claimed by the insurgent umbrella group, the Islamic State of Iraq, that includes Al Qaeda in Iraq. The body of one soldier was later found in Iraq's Euphrates River, the U.S. military has said, but the other two remain missing.

The 10-minute, 41-second video shows black-and-white, nighttime footage of what the group said was the ambush that led to the soldiers' capture. But this footage was grainy and unclear.

Gunshots could be heard in the video, which at the end shows close-ups of two identification cards.

A U.S. official said the military ID cards appeared to be authentic, but more analysis was needed to confirm this.

Family friends of the missing men said the U.S. military briefed relatives about the video over the weekend.

SITE Institute, which monitors terrorist websites, did not say how it obtained the video. The logo of media production house of the Islamic State of Iraq appears on the video.

Along with the identification cards, the footage also showed credit cards, American and Iraqi money and other personal items that they called the militants called the "booty."

The video also showed footage, apparently taken before the ambush, of three masked men standing around a stand displaying a sketch of the area, mapping out the attack plan. One of the three men, who were all dressed in black, talked to the camera and pointed to the sketch. Another stood by him carrying a gun.

"I have urged you to bring me American prisoners. We will review now a previously prepared study in our zone to bring the enemy to a good area, and with God's help we will be able to storm their place and capture them at night," said the man, whose name was not given but was identified as one of the militant group's leaders.

A prominent Islamic Web sites that commonly posts videos from militant groups including the Islamic State of Iraq said in a banner headline that it would show the video within hours, but the video has not yet appeared.

In Washington, Pentagon spokesman Bryan Whitman said he had not seen any video but heard there were "promises made that a video may be released."

"Our search continues for the missing soldiers," Whitman said.

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