For investigators, a race to decode hidden message in Austin bombings

Police in Austin are continuing their investigation of explosions that have killed two people and injured at least four others.

Most of the explosions so far were due to package bombs, but another explosion Sunday night was triggered by a trip wire and not a package bomb, the American-Stateman reported. Officials are investigating if it was created by the same person, or persons, who set off the package bombs or if it was the work of a copy-cat, the American-Stateman reported.

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If the package bombs turn out to be the work of a single person, he or she will join a tiny but grim fraternity — serial killers whose weapon of choice was an incendiary device.

The group is so small that police and psychologist’s efforts to draw meaningful conclusions about its members has met with uneven success. An FBI profile of the Unabomber identified him as an uneducated man in his 30 or 40s who probably worked menial jobs. But Ted Kaczynski was a 53-year-old hermit who held several advanced college degrees.

Even within the minuscule group of deadly serial bombers, there are important distinctions, experts said.

Some of the killers identified by forensic crime researchers selected their targets carefully. Thirty years ago, Walter Moody had a bomb delivered to an Alabama judge he felt was responsible for his misfortunes.

Other killers saw their deadly explosives as a dramatic protest against particular groups, with the individual identities of their victims apparently unimportant. In England, David Copeland’s 1999 bombs targeted blacks, Asians and gays.

Still, researchers have identified some broad characteristics that police turn to in an effort to identify deadly detonators. All have been white men. While they have varied educational attainment, they were of above-average intelligence and mechanically inclined.

Almost always, they were furious.

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