BAGHDAD, Iraq — Defense Secretary Donald H. Rumsfeld, making a surprise visit to Iraq aimed at containing the prisoner abuse scandal, said Thursday administration lawyers are advising the Pentagon not to publicly release any more photographs of Iraqi prisoners being abused by U.S. soldiers.

"As far as I'm concerned, I'd be happy to release them all to the public and to get it behind us," Rumsfeld told reporters traveling with him from Washington. "But at the present time I don't know anyone in the legal shop in any element of the government that is recommending that."

The government lawyers argue that releasing such materials would violate a Geneva Convention stricture against presenting images of prisoners that could be construed as degrading, Rumsfeld said en route to the Iraqi capital on a trip that was not announced in advance due to security concerns.

Rumsfeld was accompanied by Gen. Richard Myers, chairman of the Joint Chiefs of Staff, and several lawyers on a trip designed to reassure U.S. troops that the prisoner abuse scandal has not weakened public support for their mission and to get firsthand reports from the most senior commanders.

The Pentagon officials arranged meetings with the top U.S. commander in Iraq, Lt. Gen. Ricardo Sanchez, and other senior commanders.

Sanchez told reporters accompanying Rumsfeld that it appears Abu Musab al-Zarqawi, an associate of Osama bin Laden believed to be behind a wave of suicide bombings in Iraq, was responsible for killing Nicholas Berg, a young American beheaded by hooded men in an execution shown in a video posted on the Internet.

"All indications are that is the case," said Sanchez. Asked whether he meant Zarqawi personally carried out the execution, Sanchez said, "All indications are he did it."

Later, however, Sanchez said it wasn't clear that Zarqawi was present at the killing. "I don't know whether he was personally holding the knife or in the room," Sanchez said. "I do not know that."

Asked about Zarqawi's whereabouts, the general said, "We believe he's moivng around the country."

Rumsfeld's trip followed President Bush's visit Monday to the Pentagon, where he got an update from commanders in Iraq and declared his unwavering support for Rumsfeld, who has taken a lot of criticism from members of Congress for his handling of the scandal. Some Democrats have called for his resignation, but Rumsfeld gave no indication Wednesday that he was considering quitting.