Photographs acquired by Reuters and taken about an hour after the U.S. assault on Osama bin Laden's compound in Abbottabad in Pakistan show three dead men lying in pools of blood, but no weapons.

The photos, taken by a Pakistani security official who entered the compound after the early morning raid on Monday, show two men dressed in traditional Pakistani garb and one in a t-shirt, with blood streaming from their ears, noses and mouths.

The official, who wished to remain anonymous, sold the pictures to Reuters.

None of the men looked like bin Laden. U.S. President Barack Obama decided not to release photos of his body because it could have incited violence and used as an al Qaeda propaganda tool.

"I think that given the graphic nature of these photos, it would create some national security risk," Obama told the CBS programme '60 Minutes'.

Based on the time-stamps on the pictures, the earliest one was dated May 2, 2:30 a.m., approximately an hour after the completion of the raid in which bin Laden was killed.

Other photos, taken hours later at between 5:21 a.m. and 6:43 a.m. show the outside of the trash-strewn compound and the wreckage of the helicopter the United States abandoned. The tail assembly is unusual, and could indicate some kind of previously unknown stealth capability.

Reuters is confident of the authenticity of the purchased images because details in the photos appear to show a wrecked helicopter from the assault, matching details from photos taken independently on Monday.

U.S. forces lost a helicopter in the raid due to a mechanical problem and later destroyed it.

The pictures are also taken in sequence and are all the same size in pixels, indicating they have not been tampered with. The time and date in the photos as recorded in the digital file's metadata match lighting conditions for the area as well as the time and date imprinted on the image itself.

The close-cropped pictures do not show any weapons on the dead men, but the photos are taken in medium close-up and often crop out the men's hands and arms.

One photo shows a computer cable and what looks like a child's plastic green and orange water pistol lying under the right shoulder of one of the dead men. A large pool of blood has formed under his head.

A second shows another man with a streak of blood running from his nose across his right cheek and a large band of blood across his chest.

A third man, in a T-shirt, is on his back in a large pool of blood which appears to be from a head wound.

U.S. acknowledgment on Tuesday that bin Laden was unarmed when shot dead had raised accusations Washington had violated international law. The exact circumstances of his death remained unclear and could yet fuel controversy, especially in the Muslim world.

Pakistan faced national embarrassment, a leading Islamabad newspaper said, in explaining how the world's most-wanted man was able to live for years in the military garrison town of Abbottabad, just north of the capital.

Pakistan blamed worldwide intelligence lapses for a failure to detect bin Laden, while Washington worked to establish whether its ally had sheltered the al Qaeda leader, which Islamabad vehemently denies.