The massive FBI manhunt last weekend that ended in a fiery gun battle on a wooded, rural island north of here has unveiled what federal prosecutors call a scheme by a group of white supremacists to overthrow the government.

Robert Mathews, who died in the 36-hour siege, and four others arrested at the scene had been associated with a white-supremacist group in the Idaho panhandle known as the "Aryan Nations" and had plans to eliminate "Jewish influence" and other minority groups from American society, according to documents filed in federal court here.

The Federal Bureau of Investigation began investigating the group several months ago in connection with a series of crimes thought to be the work of a group of white supremacists. An unidentified informer who infiltrated the group provided the FBI with information linking it to three armed robberies in Seattle and northern California that netted more than $3 million.

The showdown began early Friday morning when more than 60 FBI agents swept through the pastures and woods of Whidbey Island, a 50-mile-long body north of Seattle, and surrounded three cabins on a bluff overlooking Puget Sound.

The agents closed shipping lanes near the island until late Friday evening and halted air traffic as the manhunt progressed. FBI agents negotiated with the activists and arrested four Friday on charges of harboring a fugitive.

But Mathews, 31, alone and heavily armed in one of the houses, refused to come out. FBI agents, some wearing camouflage, their faces blackened, waited in the woods through the damp, cold night while negotiations continued.

Saturday afternoon, the FBI fired teargas into the house and later attempted to enter it to arrest Mathews. Agents were met with gunfire and retreated. As the second day of the siege gave way to darkness, the FBI fired flares into the house to illuminate it. The building caught fire and quickly burned to the ground with Mathews inside as exploding ammunition kept the agents at bay.

A badly burned body taken from the ashes was tentatively identified from dental records as Mathews.

Randolph George Duey; Robert E. Merki; his wife, Sharon K. Merki, and a man identified as "John Doe" but also known as Bartlett Duane Udell and Ian Roy Steward were charged in U.S. District Court in Seattle with harboring Mathews.

Three members of the group are still at large.

During the arrest of the four activists, FBI agents seized a briefcase bearing Duey's name that contained a document dated Nov. 23, entitled "Declaration of War," said Assistant U.S. Attorney Gene Wilson.

The document declares "war" on various elements of society and was signed by Mathews, Duey and Robert Merki in the name of the "Aryan Resistance Movement," according to court papers.

The informer said Mathews invited him to join the group and told him about his plans.

The group's bible, according to the informer, was "Turner's Diaries" by William Pierce, which was published by the National Alliance, an East Coast right-wing association.

The book contains fictional "diaries" written by a man named Turner, who details a supposed takeover of the United States by white supremacists.

The diaries describe a group called The Order that undertakes its revolution by funding itself through robberies, counterfeiting and other crimes. The next step, according to the book, is to launch terrorist attacks, including bombings and assassinations, against public officials, public offices, energy facilities, communications systems, newspaper offices and television and radio stations.

The book lists The Order's enemies as Jews, blacks, other minorities, conservatives unwilling to take drastic steps and liberals, said FBI special agent Norman Stephenson.

The revolution in the book begins in 1991 and ends successfully after eight years with the murder of many people, the destruction of the "liberal Jewish press," the bombing of FBI headquarters, the obliteration of Israel with nuclear weapons and the death of the fictional Turner in a suicidal nuclear attack on the Pentagon, Stephenson said.

(nited Press International reported that the Aryan Nations Church of Hayden Lake, Idaho, issued a four-page, typed letter that it claimed to have received Saturday. The group said it contained Mathews' apparent description of his years of conflicts with federal authorities and vowed to "press the FBI and let them know what it is like to become the hunted."

The letter said Mathews worried his 3-year-old son, Clint, "would be a stranger in his own land, a blond-haired, blue-eyed Aryan in a country populated mainly by Mexicans, mulattoes, blacks and Asians."

[Mathews, after leaving Aryan Nations, formed the "White American Bastion," UPI reported.]