An unfinished novel by a scientist being scrutinized in last fall's anthrax-by-mail attacks centers on a terror scheme to spread deadly bacteria in Washington, but the story written in 1998 differs in important ways from recent real-world events.

The 198-page novel, mostly finished, describes a paralyzing attack against the White House and Congress in which dozens of people sicken or die, including the fictional president and top congressional leaders. But the unpublished book, on file at the U.S. Copyright Office, does not involve anthrax or mailings.

The co-author, former Army biological weapons researcher Steven J. Hatfill, is one of about 30 scientists who have drawn the attention of law enforcement officials investigating in the attacks, although only Hatfill's name has become public.

Hatfill, 48, has denied any role and criticized the FBI and news media for engaging in what he described as personally damaging speculation and innuendo.

Hatfill's novel, Emergence, has raised suspicions at the FBI. A U.S. law enforcement official on Tuesday characterized the work as an "interesting coincidence at this point." The FBI found a copy of the novel on Hatfill's seized computer.

It was registered for a copyright in 1998 by Roger Akers, a friend of Hatfill's who said Tuesday that he had proofread it for Hatfill and, with his permission, copyrighted it in both their names.

Hatfill's fictional villain is a Palestinian terrorist, Ismail Abu Asifa, paid by Iraq to launch a biological attack against Washington. The novel opens in Antarctica, where 10 members of a South African research team die from a strange sickness.

"Eight years later, a similar disease sweeps with explosive effect through the members of the U.S. congressional House and Senate," Hatfill wrote in the opening synopsis. "The nation's leadership is paralyzed and panic ensues as members of the executive office begin to show symptoms."

Asifa flies from England to Washington Dulles International Airport planning "to strike terror deep into the heart of the most powerful nation on Earth."

Once in Washington, Asifa buys supplies for $387 to grow bubonic plague bacteria -- "not a high price to strike terror in the government of a country this large." The bacteria in the attacks is yersinia, not anthrax.

Hatfill's villain infects the White House using a sprayer hidden inside a wheelchair during a public tour. The president is sickened before he departs for a trip to Moscow, and within days the illness spreads to top congressional leaders.

In his plot, the White House becomes the "House of Death."

But Asifa also accidentally infects himself and ultimately stumbles into the path of a car, dying six days later in a hospital.

"For all its wealth and power, the United States ... was actually an incredibly easy target for biological terrorism," Hatfill wrote. But Hatfill noted that U.S. experts were sufficiently well trained to detect attacks that his villain "would probably have only enough time to perform one attack and observe its early effects."

"It was unlikely with his present resources, that he would be able to kill more than a few hundred people at most," Hatfill added.

Also Tuesday, the FBI in New Jersey showed merchants near a mailbox that tested positive for anthrax exposure the photograph of a man and asked if they had seen him in the area last fall. The identity of the man was not known.

The idea for the novel was hatched several years ago at a dinner party where a group of journalists and former military men got to talking about bioterrorism, said Pat Clawson, a friend of Hatfill's who was there.

"We started kicking it around, that would be a cool novel to write -- let's have a bioterrorism attack on Washington and Congress," said Clawson, who is serving as Hatfill's spokesman.

The FBI has searched Hatfill's apartment in Frederick, Md., twice, as well as his car, a storage locker in Florida and the home of his girlfriend.

Law enforcement officials have described Hatfill as a "person of interest," not a criminal suspect.

While declaring his innocence publicly this week, Hatfill emphasized that his background is in the study of viral diseases such as Ebola, not bacterial diseases such as anthrax.

Hatfill previously worked at the U.S. Army Medical Research Institute at Fort Detrick, Md., once home to the U.S. biological warfare program and repository for the Ames strain of anthrax that was used in the attacks.