The FBI confirmed that its agents had conducted the searches, but refused to comment on whether the investigation targeted a particular suspect or led to any new insights into the anthrax attacks.
Yesterday, several dozen agents, some in protective suits, searched for new clues.
"The FBI and U.S. postal inspectors are conducting searches at multiple locations in New York and New Jersey," said Joe Parris, a supervisory special agent at FBI headquarters in Washington. "These searches are related to the FBI's ongoing investigation into the origin of the anthrax letters mailed in September and October of 2001."
Agents searched two homes in the upstate New York town of Wellsville that belonged to Dr. Kenneth M. Berry, according to the Associated Press. Berry is a former president of the American Academy of Emergency Physicians and in 1997 founded PREEMPT, an anti-terrorism organization.
They also searched a bungalow along the New Jersey shore with a telephone listed as belonging to "W. Berry." Neighbors told reporters the agents left carrying several garbage bags filled with bulky contents.
Law enforcement officials said they were not planning arrests and that the searches were not related to this week's heightened terrorism alerts in New York and Washington and New Jersey.
"There is no present danger to the public health or safety," Parris said.
Several hours after the searches began, Berry was arrested at the White Sands Oceanfront Resort and Spa in Point Pleasant Beach, N.J., on four counts of simple domestic assault after the police said he had punched his girlfriend and her daughter. Berry posted $10,000 bail. He told reporters he did not know why agents had searched his property and added, "We are at a very dangerous crossroads in American history."
FBI anthrax investigators shut down several bacteriology labs at the Army's biodefense center at Fort Detrick for a week last month to conduct tests in connection with the investigation.
Though the bureau would not reveal the nature of the work, outside scientists speculated that they might be hunting for stray spores of anthrax that match the exact genetic fingerprint of the spores used in the attacks.
The FBI has contracted with 19 government and private laboratories to study the powder and develop new techniques in the field of bioforensics, which uses genetic, chemical and other tests on microbes to try to trace them to a source.
Berry was quoted by USA Today in December 1997 as advocating wide use of anthrax vaccines. "We ought to be planning to make anthrax vaccine widely available to the population starting in the major cities," he said, according to the newspaper.
Earlier that year, Berry had founded PREEMPT. According to the group's Web site, it advocated training 200,000 local "primary responders" to deal with possible future terrorist attacks.
In a 1997 talk in Richland, Wash., Berry discussed a hypothetical anthrax attack on San Francisco, describing in detail the inadequacies of antibiotic supplies and hospital beds to handle such an attack. "Thus, to say this anthrax scenario would be a disaster is an understatement," he said, according to a text on the PREEMPT Web site.
According to a biography on the Web site, former Sen. Sam Nunn of Georgia once said Berry "has been one of the leaders with the emergency medical community in recognizing the potential threat of the use of weapons of mass destruction against American cities."
The biography said Berry was president of the American Academy of Emergency Physicians and director of emergency services at Jones Memorial Hospital in Wellsville. He said he had "considerable experience in forensic investigations of aircraft accidents" and had "given many lectures on bio-ethics issues."
But in 1999, Berry was charged with two counts of second-degree forgery for allegedly signing the forged will of another physician, Dr. Andrew Colletta, who had died of an apparent heart attack. In May 2000, Berry pleaded guilty to disorderly conduct and was fined $250 and the forgery charges were dropped, according to local news reports.
On Sept. 28, 2001 - 10 days after the first anthrax letters were mailed - Berry applied for a patent on a "surveillance system and method for identifying chemical, biological or nuclear attacks." The patent was granted last March, according to U.S. Patent Office records.
Berry appears to have remained active as a speaker promoting his solutions to the bioterrorism threat. Posted on his Web site is a June 2004 slide-illustrated lecture he gave in Gothenburg, Sweden, proposing an international project to combat bioterror.
Nothing on the Web site indicates whether Berry has ever worked directly with anthrax in a laboratory. The Ames strain of anthrax used in the attacks was originally identified by Army researchers at Fort Detrick in 1981, where it became the favored strain for testing vaccines. Since then it has been shared with at least a score of labs in the United States and overseas.
Sun staff writer Scott Shane, and David G. Savage of the Los Angeles Times, a Tribune Publishing newspaper, and the New York Times News Service contributed to this article.