It was their chance for revenge, and the men of the Wafi tribe took it. They captured and interrogated the man they knew as Omar, an officer in the secret police of ousted Iraqi president Saddam Hussein. Then, a dozen or so men of the tribe lined up in front of him with their Kalashnikovs and shot him dead.

"We executed him," said Sabah Wafi, who was among them. "Even when we were shooting him, he wanted Saddam, he wanted the regime. He was saying that Saddam is going to stay and the Iraqi government is going to stay and they are going to kill you."

The shooting marked another episode in a long cycle of violence against and revenge by the Marsh Arabs who live in this dry and desolate village about 45 miles north of Basra. Their tribe of about 1,000 members has been forcibly resettled from the marshes between the Tigris and Euphrates rivers that were their ancestral homeland, and over the years many of them have been arrested and tortured, executed and exiled by Hussein's government.

For years, they have been in a state of near-permanent guerrilla warfare against the government. So when four Iraqi military vehicles rolled into Shinana 10 days ago, they fired back, killing nine Iraqi soldiers and secret police officers in the ensuing firefight and capturing Omar. As a secret police officer, Omar had regularly come to the village to take men away, including Sabah's brother Salih, who never came back.

The Wafis, and the rest of the Marsh Arabs, have lost relatives, homes and their way of life in the marshes. "There are thousands of Omars like this," said Ali Hachi Wafi, one of the tribe's leaders. "They used to hang us, to take down our homes. They used to come and kill our men."

And their story offers but a glimpse of the devastation wrought by Hussein's government across the once-rich marshlands of southern Iraq. Until 1991, as many as 250,000 Marsh Arabs, or Madan, still lived in the vast network of wetlands, part of a unique subculture that has existed for 5,000 years.

But today, the mostly Shiite Marsh Arabs are believed to number as few as 40,000 after the Iraqi government systematically drained their marshes, forcibly resettled them and launched a campaign of political repression.

Accused of harboring army deserters and Shiite rebels in their waterways, the Marsh Arabs came under particularly harsh attack by the government after the 1991 Shiite uprising following the Persian Gulf War.

Physically, the marshes are a wasteland now, with just a few glints of water and stands of tall reeds by the roadside as reminders of what was before. The United Nations Environmental Program in 2001 called it "one of the world's great environmental disasters," and experts have calculated that as much as 90 percent of the 7,700 square miles of marshlands no longer exist because of drainage and upstream damming.

Human Rights Watch said in a report in December that what happened to the Marsh Arabs was a "crime against humanity," and demanded an international tribunal to investigate whether acts of genocide were committed by Hussein's government here.

But until the fall of the Iraqi government last week, independent observers had no way to record the testimony of those Marsh Arabs who remained in their devastated land, relying on reports of those who fled the country and Marsh Arabs interviewed by journalists under the scrutiny of government minders.

Today, they were able to talk openly in Shinana, and the words spilled out. They told of government bulldozers that came to destroy 18 of the houses in the village last year, of prisons where many of the men spent years, and of the executions of their brothers and sons and fathers.

They also recalled the marshes where Sheik Qathem Wafi, the tribe's 72-year-old leader, grew up and where they spent their days on boats, fishing and hunting small game. Now the tribe's marshes, which were once less than four miles away, no longer exist. "There's no marshes anymore," the sheik said. "Saddam closed all the marshes. Now, there's no water and no lands for us."

Their village, without electricity and water, lies near Highway 6, one of the main roads north to Baghdad from Basra. It is a barren place of sick-looking children where a half-naked little girl tottered toward a car this morning, with a bare bottom and a gas mask covering her face. There is no work for the men.

Inside the sheik's reception room, the window panes were cracked or shattered. A group of the tribe's leaders crowded chaotically into the stuffy chamber to recount what their lives had been like under Hussein. In the fragments of individual stories and collective experience emerged a picture of a tribe and a way of life under siege by the Iraqi government.

Asked how many of them had been in prison, 15 of about 30 men in the room raised their hands. Eleven raised their hands when asked if any of their closest male relatives had been killed. Nine said their homes in the village had been destroyed in recent years. No one could give an overall count of the number of men dead or missing from the tribe over the course of Hussein's three-decade rule, though Ali Hachi Wafi estimated the total was about 60.

The Wafi men, Shiite Muslims, said they had been banned from observing their religion until last Friday, when their imam was free to preach for the first time in years and gave a talk "thanking God and the coalition forces for giving us freedom," as the sheik put it.

During the Iran-Iraq war in the 1980s, the Marsh Arabs fought against the Iraqi government. "We fought as individuals, not with Iran, not with Iraq," the sheik said. That set off one round of government repression; another came after the 1991 rebellion, the tribesmen said.

More recently, fighting broke out across Iraq's Shiite south after the 1999 assassination of Grand Ayatollah Mohammed Sadiq Sadr, a prominent Shiite cleric in the Muslim holy city of Najaf.

Afterward, government forces came into the village with bulldozers and destroyed houses of those believed to be leading the opposition. "They have destroyed 40 houses here since 1999 when they executed Sheik Sadr," Ali Wafi said.

In May, Ali al-Sadoon, a top-ranking Baath Party official in Basra, and several government tanks came to arrest one of the men. The Wafis grabbed their Kalashnikovs -- rifles they said they had obtained from army deserters -- and began firing. They did not kill anyone. Four men from Shinana were arrested and not seen again, according to the sheik.

Many of the men, including the sheik, said they had served time in Hussein's jails. Often, the men seemed to have been deemed suspect and arrested because other family members had already been taken. Hamad Mesham Badr Wafi's brother and two cousins were executed in the 1980s for deserting the Iraqi army. He was arrested twice as well, spending four years in the notorious Abu Ghraib prison near Baghdad. He said his jailers told him he was arrested "because we are against the Baath Party and because my brothers ran away from the army."

For Sabah Wafi, the capture of secret police officer Omar this month was a chance to confront one of the tribe's many jailers.

Sabah said his 16-year-old brother Salih had been arrested in 1998 by Omar and then executed. Sabah was taken away by Omar that same year, and recalled he was taken to a secret police building in Basra and tortured by Omar and another man. "They tortured me with electricity. They used to heat up a metal thing and make me sit on it," he said. "When they tortured me, they used to have fun and drink alcohol."

The Wafis immediately recognized Omar when the Iraqi military vehicles came to the village 10 days ago. The soldiers accused them of collaborating with the U.S. and British forces, they said. "They came for us and started shooting at us," the sheik said, "so we shot at them."

When Omar was captured, he was interrogated, just as he had interrogated some of them over the years. He told them that the secret police forces were there to clear the main road for fleeing Iraqi Gen. Ali Hassan Majeed, Hussein's cousin who had been entrusted with leading the defense of southern Iraq against the Americans. Then he was killed.

"Omar killed one of our family," Sabah Wafi said. "Anyone we see who killed one of us, if we catch them, we're just going to kill them."

Sheik Qathem Wafi, a Marsh Arab tribal chief, left, gathers with his clan in Shinana. "Saddam closed all the marshes," the sheik said. "Now, there's no water and no lands for us."Sheik Qathem Wafi, center left, said he and countless other Marsh Arabs spent time in Hussein's jails.Children in southern Iraq carry cases of water as allied forces distribute fuel and water to the villages of the Marsh Arabs, who lost relatives, homes and their way of life under Saddam Hussein's rule.