ALEXANDRIA, Va. - Stepping up his counteroffensive against FBI anthrax investigators who have targeted him, Dr. Steven J. Hatfill released documents yesterday showing that he worked long hours in Virginia the days the contaminated letters were mailed in New Jersey last fall.

In his second public statement in two weeks, Hatfill accused the FBI of bungling the high-profile investigation of the bioterrorist attack that killed five people and then pursuing him publicly in a cynical attempt to demonstrate progress. He also offered to take blood tests and give handwriting samples to prove his innocence.

Hatfill singled out Attorney General John Ashcroft for publicly naming him as a "person of interest" in the anthrax investigation as recently as last week. Hatfill's attorney, Victor M. Glasberg, released copies of formal misconduct complaints he has filed with the Justice Department against Ashcroft and FBI agents pursuing the case.

"This assassination of my character appears to be part of a government-run effort to show the American people that it is proceeding vigorously and successfully with the anthrax investigation," said Hatfill, his voice occasionally breaking with emotion. "I want to look my fellow Americans directly in the eye and declare to them, 'I am not the anthrax killer.'"

But in a curious aside, Hatfill said he believes he will be charged with some crime unrelated to the anthrax mailings by investigators eager to save face and to "justify their massive financial expenditure arising out of their pursuit of me." He did not specify what crime he might be charged with, but told the throng of reporters outside Glasberg's office: "Remember, please, that you heard this from me first."

Hatfill, 48, is a physician and bioterrorism expert who worked at the Army biodefense center at Fort Detrick from 1997 to 1999. The FBI has conducted two highly publicized searches of his Frederick apartment. The agency has also searched a rented storage unit in Florida and his girlfriend's apartment in Washington. He released photographs yesterday showing what he said was the disarray left behind after the search of the belongings of his girlfriend, whom he did not name.

FBI agents have confiscated his passport, travel records, calendars and other personal documents, according to Pat Clawson, a friend and former reporter acting as his spokesman.

"I am openly followed by FBI agents in cars and on foot, 24 hours a day," Hatfill said. "Going to the store for a pack of gum yields a parade of FBI cars, sometimes following me as closely as two to four feet from my rear bumper."

In his first public statement Aug. 11, neither Hatfill nor his attorney would answer questions as to his whereabouts at the time of the mailing of anthrax-laced letters in New Jersey.

Yesterday, they released a time sheet from Science Applications International Corp., the defense and CIA contractor in whose McLean, Va., office Hatfill worked until March. The sheet shows that on the days when the letters were probably mailed, Sept. 17 and 18 and Oct. 8 and 9, Hatfill put in 14, 13.5, 13, and 11.25 hours, respectively.

Hatfill acknowledged that even those long days would have left him time to drive to New Jersey overnight, mail the letters and return before the workday began. "I have little to say about nonsense of this sort," he said. "I was living and working in the D.C. area the entire time when the anthrax letters were mailed."

Hatfill said he has invited the FBI to test his blood for anthrax antibodies, suggesting that a low reading would be evidence that he had neither recent exposure to the bacteria nor recent vaccination. But because he was given an anthrax vaccination as recently as 1999, his blood might still contain some antibodies, so it is unclear whether such a test would be definitive.

Hatfill also asked the FBI to take a handwriting sample and compare it to the writing on the letters. He said he would waive privacy claims and insist that the FBI make public all results of blood and handwriting exams.

Hatfill and Glasberg blasted the FBI for some of its recent tactics, in some cases repeating criticisms leveled by others.

For example, after anthrax spores were recently found in a mailbox in Princeton, N.J., agents showed merchants in the area a photograph of Hatfill, asking them whether they had seen the man last year. But experts on witness identification say such a procedure is seriously flawed, considering Hatfill's face was recently on television and in newspapers. Justice Department guidelines call for witnesses to pick a suspect out of an array of several photographs of different people.

Hatfill also criticized the FBI for waiting seven months before calling on the scientific expertise of William C. Patrick III, a veteran of the Army's old offensive bioweapons program who specialized in dry powder weapons. As The Sun reported last year, the bureau took months to talk to any of the weapons program veterans, even though about two dozen who are still living actually manufactured weapons-grade anthrax powder throughout the 1950s and 1960s.

FBI spokesmen did not return calls seeking comment last night.

At the news conference, Hatfill strongly criticized Nicholas Kristof, a New York Times columnist who has written about him several times, accusing the FBI of "lethargy" and urging investigators to pursue clues about a scientist he called "Mr. Z." In his most recent column on the subject, published Aug. 13, Kristof acknowledged that Hatfill was "Mr. Z" and reported, without attribution, that Hatfill had failed three polygraph tests since January.

Hatfill called that allegation "a total lie" yesterday, saying he has been given only one polygraph examination by the FBI and was told he had passed.

Hatfill's spokesman, Clawson, said Kristof had failed to seek comments from Hatfill or his attorneys before making allegations against him. He said Kristof was guilty of "journalism malpractice at its worst."

Correspondence released yesterday showed that The New York Times declined to publish Glasberg's letter on the issue, saying it was too long. The Times' opinion page also rejected the letter, and Kristof declined to run it in his column.

Reached at his Scarsdale, N.Y., home last night, Kristof said only: "You can quote me as saying I stand by the columns."

Glasberg would not comment on evidence that Hatfill embellished his resume with a Ph.D. degree he did not earn and an Army Special Forces unit he did not serve in. But Glasberg suggested that the resume inaccuracies are real, saying, "I've seen a whole lot of resumes that are, how shall I put it, expansive."

Glasberg linked his client's problems to those of men being held for months without charges in connection with the Sept. 11 investigation.

"These are dark times for civil liberties," he said.