The Army said Wednesday its investigators could not confirm that grisly photographs of purported Iraqi war dead on an Internet site were posted by U.S. soldiers, a case that has stirred concern at the Pentagon.

Paul Boyce, an Army spokesman, said the Army's Criminal Investigation Division (search) in recent days concluded from a preliminary inquiry that there was insufficient evidence to pursue felony charges.

Boyce and other officials said that while no criminal investigation would be pursued based on currently available evidence, disciplinary action may be taken against individual soldiers if it can be verified that they used government computers to transmit digital photos of Iraqi war dead. Such an act could be deemed a violation of Article 134 of the Uniformed Code of Military Justice, which proscribes behavior that undermines good order and discipline or brings discredit to the military.

Gen. Peter Schoomaker (search), the Army chief of staff, sent a message Wednesday to soldiers in the field reminding them of guidelines issued by the Defense Department and the Army regarding "Internet safety." He referred mainly to prohibitions on posting information or photos that jeopardize troop security. He did not mention the corpse photos, and spokesmen said his message was not in reaction to news stories this week describing the Web site that offers access to online pornography in exchange for corpse photos.

Some of the photos show dismembered corpses, described in accompanying Web postings as Iraqis killed in U.S. attacks. Some show what appear to be internal human organs; others show what look like charred human remains.

Boyce said Army investigators could not verify that U.S. soldiers were involved because the Web site postings were anonymous and investigators were unsure of the authenticity and origin of the photos. He said the matter had been referred to U.S. commanders in Iraq.

"We have no bona fide evidence that the U.S. military is behind this," said another Army spokesman, Col. Joseph Curtin. He added that it's a matter of concern, nonetheless, because any use of photographs or U.S. military computers to disrespect the war dead would violate good order and discipline in the military ranks.

The Council on American-Islamic Relations said Tuesday it wrote to Defense Secretary Donald H. Rumsfeld objecting to the practice, which it said may violate international laws of war, and urging the Pentagon to stop it.

"This disgusting trade in human misery is an insult to all those who have served in our nation's military," wrote Arsalan Iftikhar, the group's legal director.

Bryan Whitman, a Rumsfeld spokesman, said Wednesday the matter is being taken seriously.

"This does not represent the values of the United States military," Whitman said. "It's a despicable practice that is unacceptable."