Life science researchers at Oregon Health & Science University (OHSU) in Portland are all too familiar with the drill. A recent target on the extremist hit list: Dr. Miles Novy, a medical doctor who treats OHSU patients and conducts research on non-human primates to study premature birth. In December, Novy awoke to see both of his cars vandalized and doused with spray paint. The word “sadist” appeared on one car, “A.L.F.” on the other. Months earlier, another target, Dr. Eliot Spindel, found the slogan “ALF Eyes on You” scrawled across his garage door. ALF took credit and followed the direct action with a communiqué, threatening to firebomb Spindel’s Portland home.

OHSU spokesman Jim Newman calls the threats “very ugly, very disturbing,” and “increasingly menacing.” But Newman and others hesitate to use the word “terrorism.” “What occurs in the scientific community is not the same,” he says. “But when someone stands on your front lawn and says, ‘I know where you live,’ it can be terrorizing. Obviously, there are various levels of terrorism. This is not 9/11 terrorism, but clearly these incidents are intended to create terror in the targets.”

Of greatest concern, law enforcement and industry leaders say, are the increasing number of extremist attacks on “tertiary targets”—the banks, insurers, investors, and equipment suppliers that do business with those who conduct animal research. The attacks, once reserved for corporate offices and research labs, have become more personal and menacing in the past two to three years, targeting victims at home. “The trends are clear and cause for alarm,” says Frankie L. Trull, president of the Foundation for Biomedical Research (FBR), a Washington, D.C.-based public policy group that, among other things, tracks illegal acts against biomedical researchers. “There has been a dramatic increase in both the number and severity of attacks.”

“It is one thing to write concerned letters or hold peaceful demonstrations,” John E. Lewis told Congress during testimony on Capitol Hill while he was Deputy Assistant Director of the FBI’s Counterterrorism Division. “It is another thing entirely to construct and use improvised explosive or incendiary devices to harass and intimidate innocent victims.” Lewis is now head of all FBI operations in Arizona.

The FBI concedes that members of the extremist movement are difficult to track, arrest, and prosecute. They often commit actions wearing masks and camouflage that hide their identity. In general, animal rights extremists tend to be white, well educated, and hail from a middle- to upper-class family. But as perpetrators, they operate in cells, or as autonomous splinter groups with no formal structure, membership, or organizational hierarchy. Yet there is a thread of cohesion in the movement. Extremists are well trained to understand the letter of the law and its limits. Aided by the Internet and disposable mobile phones, they are savvy in their use of secrecy and security measures that help them avoid capture. As one extremist website has suggested, “Never discuss illegal activity indoors, over the phone, or email.”