Federal law-enforcement officials now believe the two brothers suspected in the June 18 arson of three Sacramento-area synagogues may have played a role in a possible nationwide conspiracy to provoke a race war.

The investigators disclosed their suspicions in a meeting Thursday of last week in Sacramento, attended by both Jonathan Bernstein, Central Pacific region director of the Anti-Defamation League, and Rabbi Abraham Cooper, associate dean of the Simon Wiesenthal Center in Los Angeles.

"They are trying to turn over every stone," Bernstein said this week. The FBI and the U.S. Justice Department "are certainly looking at the possibility of conspiracy…And they are also looking at some specific individuals."

FBI Special Agent James Maddock, who is heading the investigation team, refused to comment, as did FBI spokesman Nick Rossi.

But, according to both Bernstein and Cooper, detectives are carefully combing computer and telephone records of members of disparate groups based in West Virginia, Idaho, Illinois, California and the Pacific Northwest. Agents, they say, are examining the days and weeks preceding the June 18 arsons, the July 1 slaying of a Redding-area gay couple, and the mass shooting on the July Fourth weekend in Illinois and Indiana.

"Proving conspiracy is tough," Cooper said, "but they're putting a lot of resources and manpower into it."

Investigators' suspicions were piqued by a letter discovered by Redding police in which Benjamin Matthew Williams, one of two brothers linked to the June 18 arsons, wrote to National Alliance leader William Pierce. In it, Williams allegedly asked the white supremacist for assignments and suggested he could bring other recruits aboard.

Lt. Bradd McDannold of the Shasta County Sheriff's Department said it is not known whether the letter is a draft, a copy or was ever actually sent.

So far, Williams, 31, and brother James Tyler Williams, 29, have been charged in connection to the deaths of a Happy Valley gay couple, whose bodies were discovered July 1.

At the Williams brothers' arraignment in Shasta County Superior Court on Thursday of last week, they pleaded not guilty to murder and related charges. The pretrial hearing has been continued to Sept. 21. They are currently being held in the Shasta County Jail.

Although the two are suspects in the synagogue arsons, they have not been charged. Their lawyers could not be reached for comment.

Investigators are also seeking two other men who have been described as looking like college students, with shoulder-length hair. The two were spotted April 25 at a Redding church passing out literature from America's Promise Ministries, an Idaho-based anti-Semitic group. Agents know the men's identities but have not yet apprehended them.

That same day, Benjamin Matthew Williams and another individual allegedly were also seen handing out identical literature elsewhere in Redding.

Another reason for suspecting conspiracy stems from a startling coincidence.

On the evening of June 18 — the same day as the arsons — 20 white supremacists and their major funders, making up a grim roster of movement leadership, met at North Idaho College in Coeur d'Alene.

According to the ADL, the meeting was attended by Carl Story and Vincent Bertollini, two men who made millions in Silicon Valley and have since bankrolled America's Promise Ministries. The pair reportedly argued vociferously that the movement should take more aggressive action before the millennium. Listening raptly were Richard Butler, head of Aryan Nations, and Escondido resident Neuman Britton, who has been named as his successor.

Until now, evidence collected by the authorities had tied the Williamses to two hate groups: the World Church of the Creator and Christian Identity.

But the alleged letter to National Alliance leader Pierce and ties to America's Promise Ministries have fueled speculation of a conspiracy among hate groups.

"Triggering a race war is certainly at the core of all of their beliefs," said Bernstein.

With such speculation about the brothers' ties, Cooper said, "the implications aren't just for Sacramento anymore.

"That they were in touch with Pierce certainly suggests a possible link, and beyond. And if in fact there were individuals moving across state lines with an intent to commit these acts, that is terrorism."

Cooper calls Pierce "the intellectual head of the racist movement in the U.S. He inspired [convicted bomber] Timothy McVeigh. He rallies his followers, predicting a race war."

Pierce authored the apocalyptic novel "The Turner Diaries" under the pseudonym of Andrew McDonald. Federal authorities say the book, in which the protagonist kicks off a race war, provided a blueprint for McVeigh's bombing of the federal building in Oklahoma City.

Pierce maintains a Web site and publishes a monthly newsletter, as well as a comic book aimed at children.

National Alliance printouts criticize the recent war in Kosovo as a Jewish scheme to cement its grip on the "New World Order" and blame it on "the entirely kosher gang around Clinton."

In such weekly diatribes as "Smell the Blood!" broadcast on his weekly "American Dissident Voices" radio program, Pierce warns of "race suicide" by allowing Jews to run the country and major media organizations. He also calls for a "brief period of bloodletting" with "all heterosexual white men and women" firing on Jews, gays and all non-white ethnic groups.

With an estimated 1,000 members, the ADL says, the National Alliance has nearly doubled in the past three years. According to the ADL, it is the largest and most active of all neo-Nazi organizations in the United States. The National Alliance has an active chapter in Sacramento.

America's Promise Ministries is an anti-Semitic church that denies the Holocaust occurred and, like the National Alliance and other organizations, warns of the dangers of Jewish leadership in politics, banking and the media.

On April 30 — the anniversary of Hitler's death — thousands of leaflets bearing swastikas and America's Promise Ministries' return address appeared at high school and community college campuses in Shasta County. Swastikas were also painted on Foothill High School in Redding.

Five days earlier, Benjamin Matthew Williams and an unidentified partner were seen snapping the same leaflets onto cars parked in the lot of Neighborhood Church in Redding. The same day, two other men were seen passing out identical fliers on cars at Little Country Church in another part of town.

The June 18 arsons targeted Congregation B'nai Israel and Kenesset Israel Torah Center in downtown Sacramento and Congregation Beth Shalom in nearby suburban Carmichael. Kenesset Israel remains homeless, and blazes destroyed the library at B'nai Israel. Vandals set fire to the bimah and damaged much of the sanctuary at Beth Shalom. Losses have been set most conservatively at $1 million — a figure that does not include the contents of any of the synagogues.

Hate literature from the World Church of the Creator was found at two of the three sites on the day of the arsons.

Redding Police Chief Bob Blankenship said he doesn't believe the Williams brothers realize what kind of trouble they're in yet.

"If I were them, I'd be very, very, very worried."