The bizarre case of the Grand China Buffet raids has ended with the dismissal of the charges and a promise not to sue.

Immigration and Customs Enforcement agents descended on the El Paso restaurants at 655 Sunland Park Drive and 9505 Viscount and on several residences Nov. 15, questioning about 40 men and women during several days in a hotel. But only six people were formally charged. Their crime: failing to give notice of a change of address within 10 days.

In January, the charges were dismissed on the condition that the defendants "waive any and all claims against the United States," according to paperwork in the case.

All actions of ICE, the FBI and U.S. Attorney's office "were done in good faith and the defendant(s) will forgo filing any civil lawsuit or related action concerning those actions," the motion stated.

Other workers who were not charged with a crime are contemplating suing, attorneys involved in the case said.

"They are still angry. Nobody told them, 'We are sorry we rounded you up, pulling you out of your houses.' They're proud people," El Paso lawyer Miguel Torres said. "Can you imagine rounding up everybody at Leo's (Mexican Food Restaurant Downtown) and ending up charging the lowest, pettiest, little offense?"

What triggered the raids is unknown because the search warrants remain sealed.

The government has said the workers, all of whom had work permits and most of whom were political refugees, went in for days of questioning willingly. The workers, however, have said they were forced. Workers have said their interrogators seemed to believe the Grand China Buffet was part of a slavery ring. They said they worked in the restaurants freely.

ICE officials said the investigation is ongoing.

"These types of cases are complex," said Leticia Zamarripa, ICE spokeswoman in El Paso.

But while the government is still holding on to some paperwork, it has recently returned all the money seized from the immigrants, lawyers said.

Some of the workers have now left El Paso. Others could not be located, and the owners of the Grand China Buffet declined to comment through an interpreter.

In January, Torres won an acquittal for defendant Xing Lin by arguing that the government could not prove that the immigrant had not filed a change of address form, since the federal government has a backlog.

"How can we know it's not sitting in a warehouse in Virginia?" Torres said he told the court.

Since 2002, the federal government -- citing potential terrorism threats -- has required the notices to keep track of immigrants.

The government had old New York addresses for Xing Lin, Xiu Hui Liu and Giu Yin Lin, old California addresses for Yisheng Wang and Guifen Luan, and an old address in Garland, Texas, for Juan Ling Lee.

After the second defendant, Yisheng, was found guilty of the charge, the parties struck a deal and all six defendants promised not to sue in return for dismissal of charges.

"It's a significant right. They really thought about it before giving it up," Torres said.

The Chinese immigrants were facing up to 30 days in prison, possible deportation and possibly years of limbo in the judicial system. They wanted to put the matter to rest, Torres said.

The case attracted the attention of civic groups in the United States, including the League of United Latin American Citizens, and media attention in China.

Yang Chenqi, the Chinese consul in Houston, intervened.

"Our focus was the way (the migrants) were treated by the government," Yang said. "We were trying to get to the explanation. Different authorities gave different explanations. Some have apologized, some gave us excuses. It appeared like a very big case. They mobilized a lot of resources. They flew in agents from all over the country. They even used a helicopter. And it turned out to be nothing."

In a separate case, one of the Grand China Buffet's owners, Shi Ming Fang, is facing charges of harboring a nephew whose visa had expired.