WASHINGTON - Scientists have determined that the anthrax powder sent through the mail last fall was fresh, made no more than two years before it was sent, senior government officials said. The new finding has concerned investigators, who say it indicates that whoever sent the anthrax could make more and strike again.
Establishing the age of the anthrax that killed five people has strengthened the theory that the person behind the mailings has a direct and current connection to a microbiology laboratory and may have used relatively new equipment. "We're still looking for someone who fits the criteria of training, knowledge, education, experience and skill," a government official said.
The dating of the anthrax as recent suggests that the person who mailed it prepared the germs and has the ability to make more without relying on old material.
"It's modern," one official said. "It was grown, and therefore it can be grown again and again."
Officials said the FBI determined that the anthrax was fresh by radiocarbon dating, a standard means of estimating the age of biological samples. It measures how much radioactive carbon a living thing has lost since it died or, in the case of anthrax spores, since they went into suspended animation.
As the case now stands, investigators say they believe that the mailer, if ever caught, will fit the profile offered by FBI behavioral scientists: a male loner with a scientific bent and a grudge against society, a man who feels comfortable in the Trenton, N.J., area, where the letters were postmarked. The investigators are uncertain whether the perpetrator is American or foreign.
The new forensic evidence about the anthrax, usually referred to as the Ames strain, has been closely held among investigators. Laboratory experts and senior investigators will meet this week with FBI Director Robert S. Mueller III to discuss the evidence in the case. Among the topics will be the results of months of sophisticated studies conducted on the anthrax contained in the letter sent Oct. 9 to Democratic Sen. Patrick J. Leahy of Vermont.
Even though they are making progress in the science of anthrax, officials acknowledge that they have no prime suspect and have not narrowed the list of possible suspects, which in fact appears to be expanding. Investigators have a list of about 50 people, which is updated periodically as possible subjects are added or deleted.
The Leahy letter, which investigators say holds new promise in their search, was the only one of the four letters recovered in the case that contained enough anthrax to permit extensive scientific testing. The sample retrieved from the envelope addressed to Leahy, chairman of the Judiciary Committee, at his Senate office address contained as much material as a sugar packet and weighed about a gram.
Along with earlier tests that showed the anthrax was an extremely fine powder that hung dangerously in the air, the scientific studies represent the leading edge of an investigation that has expanded far beyond the FBI's investigative norms. No active criminal case has a higher priority. The inquiry has consumed millions of dollars and vast amounts of manpower.
Under heavy pressure from Congress and the Bush administration to produce results in the country's first case of deadly bioterrorism, Mueller has presided over what has expanded into the bureau's second-biggest criminal case after the investigation of the Sept. 11 attacks.
The anthrax case offers a glimpse into what may be the future of criminal investigation on a vast scale in an age of biological and other sophisticated forms of terrorism.
The FBI has collected huge amounts of personal information on hundreds of thousands of U.S. citizens, combining it with a scientific arm that has moved far ahead of the Bunsen burners, fingerprints and microscopes of conventional forensic sleuthing.
The FBI and the Postal Service, its partner in the case, have turned to experts beyond their own labs.
A new high-level containment lab to hold deadly germs and a backup unit have been built at the Army's biodefense research facility at Fort Detrick.
Scientists at labs in Massachusetts, Ohio, Utah and elsewhere have invented new protocols and tests to probe the molecular structure of the anthrax - a task complicated by the possibility that the culprit could be among the microbiologists assisting the FBI.
Officials say every investigative technique available to the FBI has been used in the case, including round-the-clock surveillance, eavesdropping and searches conducted under the Foreign Intelligence Surveillance Act. Agents have conducted 5,000 interviews and served more than 1,700 grand jury subpoenas.
Hundreds of people have been given polygraphs. Investigators have compiled minute-by-minute chronologies of the lives of some subjects, examining their whereabouts when the letters were sent.
Forty of the FBI's 56 field offices and many of its 44 overseas legal attaches have been asked to help. The FBI has established 112 separate databases to store information about the case.
The scale of the investigation and the lack of progress in finding a suspect have prompted a number of people to criticize the FBI's approach to the case. These people, many of them science experts, have prodded the bureau to move more aggressively, unsuccessfully pushing it to narrow its focus.
So far, even the offer of a $2.5 million reward has failed to produce a breakthrough lead - even though in one case last fall, investigators said they were convinced they had their culprit. They passed the word of a pending arrest up the chain of command to President Bush, but their hopes were dashed when their quarry proved innocent. "We just can't seem to catch a break," one government official said.
Besides being one of its largest investigations, the anthrax case has also been one of the FBI's most frustrating. On Nov. 2, Mueller acknowledged at a White House news conference that the FBI was stymied and had no idea who was responsible for the attacks.
"We have not said it's domestic, we have not said it is international," Mueller said at the time. "We have not precluded any possibility."
Mueller was not the only senior official who has been impatient about the lack of progress. The anthrax case has been one that Bush has often asked about in morning briefings by Mueller and Attorney General John Ashcroft. Mueller and Ashcroft have chafed at having little to report to the president, officials say.
Although there were five victims whose manner of death was apparent, hard leads were surprisingly scarce. "We had four letters that had no evidence on them and one gram of powdered anthrax that would kill you if you mishandled it," one official said.
Agents subpoenaed pharmacy records for the names of people who obtained prescriptions for Cipro, an antibiotic used against anthrax, or anyone who obtained a vaccination, in hopes of finding someone who might have tried to ward off possible infection.
The information from those searches was fed into a database containing lists of people who were stopped for traffic violations in the Trenton area or who traveled to or from nearby airports in the days before and after the mailings.
The government's multi-agency terrorism financial review unit, which traced the origins of money spent by the Sept. 11 hijackers, was brought in to examine whether any unusual stock trading or changes in stock prices might suggest whether anyone profited from the anthrax attacks. The stocks of more than 100 companies were inspected.
But at the center of the effort was an investigation of labs that had the ability to make anthrax or had an inventory of the Ames strain. Along with that effort was a second track in which agents compiled lists of the thousands of manufacturers and distributors, primarily in the United States, of specialized equipment needed to make anthrax, such as hooded glove boxes or milling and drying machines.
Those results offer insight into the complexity of the case. One group under scrutiny is the biopesticide industry, a sector of eight primary companies that has produced a list of about 80 people who remain under investigation.
Another group is the biopharmaceutical industry, a larger grouping of more than 100 companies, which has produced a list of about 200 possible subjects. Finally, public and private labs with anthrax inventories or production capability account for another group of about 50 people who are under suspicion.
Early on, genetic testing of the anthrax in the letters yielded a major clue. The germs found in Florida, Washington and New York were all of the variety known as Ames, named after the Iowa city.
Scientists in the United States frequently used the Ames strain in their work, raising the prospect that the deadly powder was American in origin.