The purpose of the list was not immediately clear, said the official, who requested anonymity because he was not authorized to speak publicly.
Police say von Brunn acted alone in carrying out the museum attack, CBS News correspondent Bob Orr reports. But the shooting was hardly his first run-in with the law.
Von Brunn, who ran a Web site espousing his lifelong anti-Semitic beliefs from his Annapolis, Maryland home, spent six years in federal prison in the 1980s after a bizarre attempt to kidnap Federal Reserve Chairman Paul Volcker, reports Orr. He was arrested inside Fed headquarters with a revolver, sawed-off shotgun and hunting knife.
Von Brunn describes the assault with apparent pride on his Web site.
"The subject resides in my memory like old road-kill," he wrote of the capture. "What could have been a slam-bang victory turned into ignoble failure. Recalling all of this presents an onerous task. I am getting near the end of the diving board."
Von Brunn is a native of St. Louis, a World War II veteran who served in the Navy for about 14 years, worked in advertising in New York City and moved to Maryland's Eastern Shore in the late 1960s, where he stayed in advertising and tried to make a mark as an artist. He was living in New Hampshire the year of his arrest
Despite the weapons found in his bag that day, von Brunn insisted he was trying to place the board under "legal, non-violent citizens-arrest."
Von Brunn spewed hatred and drew support from other white supremacist radicals on his Web site, which featured an anti-Semitic treatise "Kill the Best Gentiles," that he said no one would publish. He decries "the browning of America" and claims to expose a Jewish conspiracy "to destroy the White gene-pool."
"It's better to be strong than right," he said in one of his dark screeds online, "unless you like dying. Crowds hate good guys."
Von Brunn also wrote, "The 'Holocaust' Religion is destroying Western Civilization. The Aryan gene-pool dies, 'unwept, unhonored and unsung."'
There are thousands of radical Web sites, and that number is growing, reports Orr.
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"We find over 10,000 in our database. The growth has been steady but there has been a spike fairly recentlyl," Mark Weitzman, of the Simon Wiesenthal Center, told CBS News.
And the spike in Web sites is mirrored by the explosive growth in the number of hate groups in America - up more than 50 percent in eight years, from 602 in 2000 to 926 last year, according to the Southern Poverty Law Center.
Civil rights groups were particularly familiar with von Brunn's virulent history.
"We've been tracking this guy for decades," said Heidi Beirich, director of research for the Southern Poverty Law Center's Intelligence Project, which tracks hate crimes. "He thinks the Jews control the Federal Reserve, the banking system, that basically all Jews are evil," she said. "He's an extreme anti-Semite."
His Internet writings say the Holocaust was a hoax. "At Auschwitz the 'Holocaust' myth became Reality, and Germany, cultural gem of the West, became a pariah among world nations," he wrote.
The attack is "further proof that anti-Semitism and Holocaust denial have not passed from the world," said Israel's information and Diaspora minister, Yuli Edelstein.
"It's the first domestic terrorist of this age that we've seen," Beirich said. "It just shows you it doesn't matter what age you are - you can be driven to violence from these belief systems."
Von Brunn remains in critical condition after being shot by a security guard. He was being treated at a Washington hospital.
Security engaged the suspected gunman as soon as he stepped inside the crowded museum and began shooting, authorities said. Guard Stephen T. Johns, 39, who is black, "died heroically in the line of duty," museum director Sara Bloomfield said.
Investigators are trying to determine how von Brunn acquired the .22-caliber rifle used in the attack, said two other law enforcement officials, also speaking on condition of anonymity.
Israeli officials and U.S. Muslim and Hispanic groups all expressed shock at the attack, which unfolded in a public space filled with records, photographs and exhibits standing as stark testament to the Nazis' killing more than 6 million Jews in the Holocaust of more than a half-century ago.
The museum was crowded with schoolchildren and other tourists, but all escaped injury.
Ashley Camp, 14, of Forsyth, Ill., on a field trip with more than 40 other students, said she heard two or three gunshots. Soon after, a security guard ordered the group to run to the exit.
"We had to sprint as fast as we could out the door," she said. "I thought it was the movie (part of a museum exhibit), but then everyone started screaming and running."
Law enforcement officials said von Brunn's car was found near the museum and was tested for explosives. They spoke on condition of anonymity, saying they were not authorized to discuss the investigation.