WASHINGTON -- Federal authorities charged James von Brunn with murder as FBI agents sifted through documents taken from the car and house of the man accused of an armed assault on the United States Holocaust Memorial Museum.

The 88-year-old von Brunn, a longtime white supremacist and anti-Semite, left behind a signed notebook in his car, found near the museum, with a note that touched on a recurring trope in right-wing conspiracy literature: a forthcoming seizure of private firearms by the Obama administration.

"You want my weapons -- this is how you'll get them," Mr. von Brunn wrote. "The Holocaust is a lie. Obama was created by Jews. Obama does what Jew owners tell him to do. Jews captured America's money. Jews control the mass media."

The note mirrored an increasingly violent rhetoric, said one associate, a self-described "white separatist" from Butler County.

"I became concerned because his e-mails were getting more and more violent in tone. We whites, or we white separatists, we're going to be rounded up and killed by Jews in the federal government. This is a widespread feeling in the white separatist community," said John de Nugent, a Rhode Island native who moved to Sarver in February 2008, where he hopes to lead a movement to create a "white safety zone" in a four-state area, including Pittsburgh.

"Jews seek to destroy White America. They created Obama to read their 'multicultural' death-message to ignorant Christian sheep. America now teeters on the brink of extinction," Mr. von Brunn wrote May 27.

Writings dating from 1999 to the weeks before Wednesday's fatal shooting at the Holocaust Museum paint a tableau of conspiracy theory, race hatred and deepening despair.

"Your tactics should be: destroy the enemy before the enemy kills you. Act now!" Mr. von Brunn wrote in one e-mail.

Mr. de Nugent said he talked by telephone with Mr. von Brunn two weeks ago. Speaking from his home yesterday, Mr. de Nugent condemned the armed attack on the museum and said in retrospect he now saw the warning signs.

"He told me he was very bitter -- that his Social Security had been slashed just about in half," Mr. de Nugent said. "He believed somebody had read his Web site and was retaliating against him for his politically incorrect opinions."

Living in Annapolis, Md., with his son, Erik, and his son's fiancee, Brandy Teel, Mr. von Brunn had been divorced for at least a decade and recently told Mr. de Nugent that he had given away his computer.

"When you start giving away things, I guess I should have realized it was a troubling sign," Mr. de Nugent said. "I think he was planning that this would be some sort of catalyst event, leading to something more."

Heidi Beirich, a researcher at the Southern Poverty Law Center in Montgomery, Ala., said the attack at the Holocaust Museum fit a pattern of extremist attacks that date from Mr. Obama's election. Among them, she noted, was the April standoff in Pittsburgh's Stanton Heights neighborhood when Richard Poplawski, a young man who has espoused racist and anti-Semitic theories as well as fears about gun seizure, was accused of killing three city police officers.

"I think we've already seen a rise in domestic terrorism and this is just the latest in the chain of events," Ms. Beirich said.

A longtime anti-Semite and Holocaust denier, Mr. von Brunn is accused of storming into the museum with a .22 caliber rifle and shooting dead a guard, Stephen Tyrone Johns. Mr. von Brunn was wounded when guards returned fire and was in critical condition at a Washington hospital.

He last attracted widespread attention in 1981, when he attempted to take members of the Federal Reserve Board hostage. Mr. von Brunn spent six years in prison for that act.

Mr. de Nugent, who ran a symbolic write-in campaign for president in 2008 and is planning to launch his own white separatist movement in the coming weeks, said Wednesday's attack could be a harbinger of deepening anger among a subset of whites convinced the United States is being taken over by a Jewish-led cabal and a black president they believe wants to seize their weapons and end their rights of free expression.

Investigative records indicated Mr. von Brunn held subscriptions and mail-order memberships to an assortment of far-right and anti-Semitic organizations, including the California-based Institute for Historical Review, and the Adelaide Institute, a far-right Australian group.

In 2004, Mr. von Brunn spent several months in Hayden, Idaho, home base of the now-defunct Aryan Nations, a longtime breeding ground for white supremacists and domestic terrorists that included The Order, a supremacist group that carried out murders and armed robberies in the 1980s.

One intelligence document shows that when they arrested racist leader Mo Gulett on charges of conspiracy to commit bank robbery in 2005, FBI agents discovered an application form for Mr. von Brunn for an Aryan Nations splinter group known as Church of the Sons of Yahweh.

The Southern Poverty Law Center also said Mr. von Brunn was affiliated with the Noontide Press, an anti-Semitic publishing house created by Willis Carto, a longtime fixture in the American far-right. Mr. Carto, however, has denied knowing Mr. von Brunn.

FBI agents searched Mr. von Brunn's apartment in Annapolis last night, evacuating the building for fear he might have booby-trapped the room he sublet from his son.

Harold Olynnger, 82, lives next door to Mr. von Brunn at Harbour Gates, an upscale apartment complex in Annapolis, about 30 miles from the Holocaust Museum.

He said Mr. von Brunn wasn't particularly friendly, but that he accepted an invitation a few months ago to have a vodka tonic with Mr. Olynnger and his wife Martha in their apartment and that the Holocaust came up in conversation.

"He said the Holocaust, the media was covering it too much. They were at the time and I agreed with him and he sat there and had a drink and that was about it," Mr. Olynnger said.

He said he never knew about Mr. von Brunn's criminal history, his hatred of Jews, his Web site or his gun.

After he learned what happened at the museum, he said he thought, "I'm living next door to this guy, my God."