Ann Clwyd, a British Parliament member who pursues Iraqi war criminals in her spare time, quietly began amassing evidence last year against Barzan Tikriti, the half-brother of President Saddam Hussein and a former head of Iraq's intelligence agency.

But as she was preparing to try to persuade Swiss authorities to arrest Barzan, he suddenly returned to Iraq last November from his home in Geneva. The pursuit of Barzan was the first secret operation by Indict, a single-issue organization founded by Clwyd and Iraqi opposition figures.

Modeled loosely on the groups that tracked Nazi war criminals to the far reaches of the globe, Indict is one of a handful of private organizations that are trying to cast a net around Saddam Hussein and his inner circle, with the moral and financial backing of the U.S. government.

Its board members include Peter W. Galbraith, a former U.S. ambassador to Croatia; Ahmad Chalabi, a key player in the CIA's botched efforts to overthrow Saddam Hussein in the early '90s; and Hamid Bayati, a leader of the Supreme Council for the Islamic Revolution in Iraq, or SCIRI, a Tehran-based opposition group that has gained access to Iranian archives on the Iraqi use of chemical weapons.

Since it was founded in Britain in 1997, Indict has compiled a list of more than 10 Iraqis that it considers war criminals for their actions during the Persian Gulf War, the Iran-Iraq War and various crackdowns on Kurdish and Shiite minorities.

While the organization has yet to secure the arrest of a single Iraqi, it got a major boost this year: the first $500,000 of a $3 million commitment from the U.S. government, part of a broader American effort to undermine Saddam Hussein's regime.

The Clinton administration, which Congress has authorized to spend $8 million to support the Iraqi opposition, is now considering giving assistance to other organizations that seek to bring suspected Iraqi war criminals to justice, including the U.S.-based Iraq Foundation, the International Monitoring Group and the Human Rights Alliance.

"We are very supportive of the Indict program and these other organizations," said David Scheffer, the U.S. ambassador-at-large for war crimes.

Better-established human rights groups, however, eschew government funding to preserve their independence and, while supportive of war crimes prosecutions in general, are skeptical about what may be seen as opportunistic alliances.

"I hate to be cynical, but the [Clinton] administration thinks there is no viable opposition [in Iraq] to provide arms to, so they are looking for ways to spend" the money allocated by Congress, said Joe Stork, an analyst at New York-based Human Rights Watch, which has long urged the U.S. government to pursue Iraqi war criminals.

Galbraith said the financial contribution shows that American officials are finally putting their "money where their convictions are."

He said Indict will use the money to collect testimony from witnesses, pay researchers and develop legal arguments. Already, he said, the University of Colorado at Boulder has 18 tons of Iraqi documents captured by Kurdish groups after the Gulf War, and Kuwait has four tons.

"The Iraqis were a bit like the Nazis or the Khmer Rouge: they recorded the minutest details," said Clwyd.

Besides Saddam Hussein, Indict's target list includes his son Uday, his two half-brothers, deputy prime minister Tariq Aziz, senior intelligence officials and Ali-Hassan al Majid, who is called "Chemical Ali" by the opposition for his alleged role in using chemical weapons.

If one of these men eventually is arrested, prosecutors will face the question of where to attempt a trial. Iraqi opposition groups say they would like the Clinton administration to push for a special U.N. tribunal for Iraq, along the lines of the tribunals for Rwanda and the former Yugoslavia. But there is strong opposition to that idea in the U.N. Security Council.

Inspired by the arrest of former Chilean dictator Augusto Pinochet in London last year on a warrant issued by a Spanish judge, Indict and other groups have been scouting Europe for sympathetic judges and prosecutors.

Last month, Indict and a Vienna city councilman, Peter Pilz, tried to persuade Italian authorities to detain Aziz at a conference in Italy. But the case revealed a woeful lack of coordination.

While Indict and Pilz, working independently and unaware of each other's efforts, sought to prepare a legal trap for Aziz, Human Rights Watch sent a letter to Italian Prime Minister Massimo D'Alema urging him to revoke Aziz's entry visa. Aziz canceled his trip at the last minute.

On Aug. 5, the war crimes hunters got a fresh opportunity with the arrival of another senior Iraqi official, Izzat Ibrahim Douri, in Austria for medical treatment. Tipped off by an informal network of Iraqi informants, Clwyd began building a case against the former ice vendor, who rose through the ranks of the ruling Baath party to become Saddam Hussein's second in command.

Pilz, a member of Austria's Greens Party and long-time advocate of the Kurdish cause, was also on the trail. Through a local Kurdish refugee network, he located potential witnesses including Aziz Dilshad, a 27-year-old woman who lived near the northern Iraqi town of Halabja when it was bombed with chemical weapons in March 1988, killing as many as 5,000 Kurdish civilians.

"We found victims in Vienna who were ready to act," Pilz said. He filed a criminal complaint against Douri with the Vienna district attorney's office on Aug. 13. But the Austrian government took no action, and Douri quickly boarded a Royal Jordanian Airlines flight for Amman.

The missed opportunity brought recriminations against Pilz.

"He jumped the gun," said Clwyd. "I felt if we had another week we would have been able to present quite substantial evidence."

The episode, according to Reed Brody, director of advocacy at Human Rights Watch, underscores the need to prepare an ironclad case before going to court. "The Austrians have friendly relations with Iraq, but if you confront them with compelling evidence, they are going to be put in a difficult position," said Brody. "We need to be in a position to act quickly."