Defense Secretary Donald H. Rumsfeld (search) defended his decision to hold a prisoner captured in Iraq without notifying international authorities, saying it was at the request of CIA Director George J. Tenet and the detainee was treated humanely.

"He wasn't lost in the system," Rumsfeld told reporters at the Pentagon. "There is no question at all ... that he received humane treatment."

The terror suspect has been held since October without being given an identification number and without the International Committee of the Red Cross (search) being notified, Pentagon spokesman Bryan Whitman said. Both conditions violate the Geneva Accords on treatment of prisoners of war.

Rumsfeld described him as an Iraqi who was a high-ranking member of Ansar al-Islam (search), a militant Islamic group believed to have orchestrated some of the bombings and guerrilla warfare in Iraq.

Rumsfeld ordered the Joint Chiefs of Staff to have the prisoner secretly detained on the day last year when Tenet made the request, Whitman said.

"The director of central intelligence requested he not be assigned an internment serial number while the CIA worked to determine his precise disposition," Whitman said.

Rumsfeld said Tenet had the authority to make the request. The defense secretary said such a call would be to prevent the prisoner's interrogation from being interrupted.

The Bush administration has argued that the Geneva Conventions (search) do not apply to suspected terrorists who do not follow the conventions themselves. But Rumsfeld and other administration officials have said the Geneva Conventions applied to all U.S. military activities in Iraq since the March 2003 invasion.

The prisoner will be given a number and the Red Cross will be formally notified soon, Whitman said.

"The ICRC should have been notified about the detainee earlier," Whitman said. "We should have taken steps, and we have taken the necessary steps to rectify the situation."

The Pentagon's admission came a day before a human rights group released a report accusing the United States of keeping an unknown number of terrorist suspects in secret lockups around the world.

A report from New York-based Human Rights First (search) said the Bush administration was violating U.S. and international law by refusing to notify all detainees' families or give names, numbers and locations of all terror war prisoners to the Red Cross.

None of that was done in the Iraqi detainee's case, Whitman said.

Keeping secret prisoners creates conditions for abuses such as the humiliations and beatings suffered by some Iraqi prisoners at Abu Ghraib, the group argues.

"The official secrecy surrounding U.S. practices has made conditions ripe for illegality and abuse," said the report from Human Rights First, formerly called the Lawyers Committee for Human Rights.

The group said the United States should immediately allow Red Cross access to all terror war detainees, notify the prisoners' families and announce the number and location of such prisoners.

The Iraqi prisoner is so far the only individual Defense Department officials have acknowledged shielding from the Red Cross. Before Wednesday's admission, Pentagon spokesmen would not confirm or deny if anyone was being held in secret.

"We've not talked about the location of specific detainees other than Iraq, Afghanistan and Cuba simply because it gets into the classified realm," Air Force Maj. Michael Shavers said in an e-mail response to questions from The Associated Press on Wednesday, before the Iraq admission.

President Bush and members of his administration have said repeatedly that all detainees are treated humanely. Pentagon officials have argued that announcing the numbers or locations of all detainees would indicate the scope of U.S. anti-terrorism efforts to terrorist groups and give them ideas of sites to attack.

The secret prisoner in Iraq is believed to be a high-ranking member of Ansar al-Islam, a radical group which had been based in northern Iraq before the U.S. invasion last year. U.S. officials believe the man was involved in attacks on coalition troops, Whitman said.

Deborah Pearlstein, a co-author of the Human Rights First report, said the United States needs to stop keeping secret prisoners altogether.

"There's a lot of unnecessary mystery surrounding U.S. detention practices," Pearlstein said Wednesday, before the Pentagon's admission.