SACRAMENTO, Calif. — A federal magistrate ordered four Hmong men charged with conspiring to overthrow the government of Laos held without bail yesterday.

In a series of back-to-back hearings here, Magistrate Kimberly Mueller ruled that each of the California men, Youa True Vang, 60, Hue Vang, 39, Chong Yang Thao, 53, and Chue Lo, 59, posed too great a danger to the community to be released.

Prosecutors contend that the men, several of whom fought the communists in Laos in the 1960s and ’70s, recently sought to purchase automatic weapons and stinger missiles from an undercover agent. The munitions were to be used in an attempt to bring down the present communist regime in Vientiane, prosecutors charge.

Defense attorneys firmly rejected the suggestion that any of the men pose a threat to Americans. “All the danger he could ever have posed was 10,000 miles away in a foreign country,” a lawyer for Youa True Vang, Steve Bauer, said. “I’m not excusing that,” the attorney quickly added.

The defense also stressed that the men fought side-by-side with Americans for years. “There was such a strong allegiance to the U.S. that they felt they did serve the United States Government,” a lawyer for Mr. Thao, Dina Santos, said.

The men in court yesterday are part of a group of nine arrested for conspiring to kill, kidnap, maim, or injure abroad, committing weapons violations, and seeking to violate the Neutrality Act, a law which can be traced back to 1794 and precludes private expeditions against countries with which America is at peace.

An attorney for Mr. Lo, Sheri Rusk, said the court should take care not to penalize the defendants simply because they may have attended meetings where other participants talked about overthrowing the government of Laos.

“These are large meetings with people expressing political dissent about a brutal regime in Laos, a communist country,” Ms. Rusk said “They are entitled to have what views they have.”

A prosecutor, Robert Twiss, said those concerns were misplaced and that none of the key gatherings involved more than a dozen people. “These are not meetings that were large political rallies. These are meetings solely and exclusively to look at automatic weapons and more heinous weapons,” he said. “There’s no political discussion here at all.”

Mr. Twiss said the loss of life would have been enormous if the coup effort proceeded. “We’re not talking about murdering one person or two persons. We’re talking about making buildings look … like they were in 9/11,” he said. “The danger is huge.”

Ms. Rusk also argued that Hmong traditions might have led some of the men to show up at sessions they had no interest in or knew nothing about. “If a leader asks you to attend a meeting, there is a deep and profound respect for that,” she said.

Magistrate Mueller said she saw some merit to that argument. “It’s one of the complexities in this case,” she said. The magistrate said she saw no direct threat to Americans, that there may have been an “indirect” danger.

Based on the charges, the law presumes bail should be denied. Magistrate Mueller said none of the men had shown they could safely be released. “There are too many unanswered questions,” she said.

A legendary leader of the Royal Lao Army’s fight against the communists and of the Hmong community in America, General Vang Pao, is among those facing charges in the case. General Vang, who has lived in recent years in Orange County, Calif., faces a bail hearing here on Monday.

The only non-Hmong charged in the case is a West Point graduate and Vietnam veteran, Harrison Jack, 60, of Woodland, Calif. He allegedly told the Hmong group he was recruiting retired members of American special operations teams to aid in the overthrow plot.

A former state senator from Wisconsin, Gary George, is identified in prosecution filings as part of the conspiracy, but he has not been charged. An affidavit filed by the government also mentions that the charged men had a conference call recently with an unnamed Congressman.

Rep. Dana Rohrabacher of Orange County, Calif., said he was not involved in that discussion, but believes the group has been singled out unfairly. “This seems to be a situation where they’re targeted because they are engaged in an effort to forcefully bring down the Laotian dictatorship,” the Republican Congressman told the Associated Press. “I don’t think that’s anything that should worry Americans, that some people who believe in democracy are trying to overthrow a dictatorship in their homeland.”

Prosecutors seem intent on protecting the identity of the undercover agent who posed as an arms dealer when dealing with the group. His name was deleted from the court’s public files. Court papers indicate that he works for the San Francisco office of the Bureau of Alcohol Tobacco and Firearms and that he was once a Navy Seal.

Any of the defendants could seek to question and cross-examine the agent as part of the bail process, but none has done so yet.