Mohamed Aweys was a teenager when he and his family fled Somalia's civil warfare over a decade ago. Now, in an austere cell in a U.S. jail, he worries that he could be deported back to that violence-wracked country, for what he calls a youthful mistake.

"I feel I would be killed in Somalia. Everyone has guns and weapons in Somalia," said Aweys, 25, a bearded, heavyset man in blue prison scrubs, speaking through a mouthpiece in the Plexiglass divider of a visitors' room.

For years, U.S. officials have deported Somalis who are in this country illegally or have committed crimes, along with tens of thousands of other immigrants sent home. But recently, lawyers have mounted an unusual challenge to that practice, arguing that Somalia is so lawless and violent that the immigrants' lives are being put at risk.

Their challenge centers on a narrow issue -- whether the Immigration and Naturalization Service needs the receiving country to accept a deported immigrant -- but it raises bigger questions about refugees' rights and the U.S. government's anti-terrorism campaign.

"There's no functioning government" in Somalia, said Pramila Jayapal, director of Hate Free Zone, a Seattle nonprofit group working with lawyers to launch a class action suit aimed at ending the deportation of Somalis. "If we send people back . . . they will be killed."

The United States has not recognized a government in Somalia since 1991, and the State Department considers it "extremely dangerous" to travel in the East African country. But immigration officials say their responsibility is to remove people who have committed crimes or are otherwise ineligible to stay.

"Many people could argue that being sent back to their home country is not an ideal situation . . . [but] millions and millions of people are living in these countries," said William Strassberger, an INS spokesman.

The Justice Department, in court papers, has maintained that this case touches on a central element of the war on terrorism. If the attorney general's powers to deport people were limited, "he would be stripped of a vital tool to protect the security of this nation's borders," department attorneys contend. The U.S. government has grown increasingly concerned that Somalia could be a base for terrorism, although the Somalis in this case are not accused of such activities.

Aweys, the son of a Somali air force engineer, fled his homeland as it was engulfed by civil war in 1991. The family won asylum in Finland, but Aweys was restless, and in 1995 he traveled to America as a tourist to visit relatives. While his visa allowed only a brief visit, Aweys, then 18, stayed on.

"I made a mistake," he acknowledged. Within several months of arriving in the United States, Aweys applied for political asylum, but failed to report that he already had won refugee status in another country.

"I was young. I didn't know" that that would be interpreted as a fraudulent claim, he said.

Meanwhile, his legal status in Finland lapsed. After his asylum claim here was denied, the INS detained him, and scheduled him to be sent back to Somalia.

On a cool night in November, Aweys and four other Somalis in the INS detention facility in Seattle received word that they were about to begin their journey to Africa. But hours later, their attorneys won a temporary stay.

Aweys's pro bono attorneys contend that under international treaties, the U.S. government cannot return people to places where they will face harm. They also point to a recent case in Minnesota, in which a judge ruled that a Somali man should not be deported because the INS lacked the required go-ahead from the receiving country.

"The silence of a non-functioning government in a lawless territory . . . simply cannot constitute 'acceptance,' " U.S. District Judge John R. Tunheim wrote.

The INS appealed that ruling. While INS and Justice Department officials won't comment on the cases, they have argued in court papers that a country provides de facto acceptance of a deported immigrant if it allows him to get off the plane.

In addition, officials say the Somalis already had the chance during their hearings to seek asylum based on fears of persecution back home.

After Aweys and the other detainees won their stay, their advocates and attorneys were deluged with calls -- from Louisiana, Florida, Utah, Texas -- from Somalis hoping that they, too, could avoid imminent deportation.

Eventually, the attorneys decided to seek a class action lawsuit for all Somalis facing deportation -- about 2,700 nationwide. Earlier this month a Seattle judge ordered the INS to stop removing Somalis until she decides whether to certify the suit, a ruling expected in January.

For Somali communities around the country, the deportations have evoked anger and dread.

"We are scared about somebody deported from here. They won't survive" in Somalia, said Geilani Hussein, an activist in Northern Virginia.

Activists say the INS has been stepping up deportations of Somalis as part of a post-Sept. 11 crackdown. Between 1997 and 2001, U.S. immigration officials say, they have sent between 22 and 47 people a year back to Somalia. This year, they have deported at least 32 and jailed 39 more for imminent removal.

Under the anti-terrorism effort, Somalis and people from other Muslim countries are considered a priority in efforts to round up foreigners who have defied deportation orders.

Most of the Somalis facing deportation were in the United States legally, either as refugees or through a government program known as "temporary protected status," which allows Somalis here without visas to apply for work permits on the ground that it is too dangerous for them to return home. However, immigrants can be stripped of their legal residency if they commit an aggravated felony.

That's the case with most of the Somali deportees.

"You can't expect to be an abuser of American law and get protection at the same time," said Strassberger, the INS spokesman.

Immigrant advocates say the law is unduly harsh. Some of the Somalis were convicted of violent acts, such as rape and assault, but others had to give up their American lives because of shoplifting, drunken driving or possessing small amounts of drugs. A 1996 law limited the ability of judges to waive deportations due to special circumstances.

For some Somalis, deportation means returning to a land they barely know.

Fuad Hassan Ismail, for example, isn't even fluent in the local language. He grew up in Yemen, the son of Somali parents, and had lived in the United States since he arrived on a student visa in 1984. He eventually entered the temporary protected status program.

In the mid-'90s, he began to get into trouble, and he was convicted of possessing drug paraphernalia and cocaine.

In 1998, after he was released from detention, Ismail completed a Salvation Army drug and alcohol rehabilitation program.

"He was saving to buy a house and get married," said Samuel Southard, administrator of the Salvation Army Adult Rehabilitation Center in Seattle. "I'd trust him with my grandkids."

Ismail said he reported periodically to the INS, as required. But the cocaine charge meant he was eligible for deportation.

Earlier this year, he was picked up at his maintenance job at the Seattle Yacht Club and whisked out of the United States with other deportees. INS officials declined to comment on his case.

"Mogadishu was crazy, wild -- there was gunfire" when he arrived, Ismail said in a telephone interview. He had only $60 in his pocket, since he hadn't had time to go to a U.S. bank before his departure, he said.

Ismail managed to get to Hargeisa, on the other side of the country, where he has relatives. But it has been impossible to find a job in the poverty-stricken area, he said, especially since he can't write Somali.

"You never know when something will erupt. There are different warlords," Ismail said. "I'm just living day by day, hoping nothing happens."

Miriam Abdi, 6, waits for her mother at a Somali-oriented grocery store in Seattle. Somalis in the United States say they are afraid to be deported.