Unabomber bombings (1978–1995)

Between 1978 and 1995, a series of sixteen mailed or hand-delivered bombs killed three people and injured 23 others across the United States. The FBI investigated the attacks under the case identifier UNABOM, short for University and Airline Bombing, after the early targets.

Hugh Scrutton, 38, the owner of a computer rental store in Sacramento, California, was killed on December 11, 1985, when a bomb left in the store's parking lot exploded. Thomas J. Mosser, an advertising executive with Burson-Marsteller, was killed on December 10, 1994, by a package bomb delivered to his home in North Caldwell, New Jersey. Gilbert Brent Murray, president of the California Forestry Association, a timber industry lobbying group, was killed on April 24, 1995, by a mail bomb at the association's Sacramento office; the package had been addressed to the group's retired former president.

Those injured included faculty, staff and students at Northwestern University, Vanderbilt University, the University of California, Berkeley, and the University of Michigan. United Airlines president Percy Wood was injured in 1980. Gary Wright was injured in February 1987 by a bomb left in the parking lot of a Salt Lake City computer store. In June 1993, geneticist Charles Epstein of the University of California, San Francisco, and Yale computer scientist David Gelernter were both seriously injured by mail bombs. A 1979 device placed in the cargo hold of American Airlines Flight 444 released smoke and forced an emergency landing.

An FBI-led task force that included the Bureau of Alcohol, Tobacco and Firearms and the U.S. Postal Inspection Service grew to more than 150 full-time personnel. In 1995 the bomber offered to stop if a roughly 35,000-word manifesto was published, and it appeared in The Washington Post in September 1995. Theodore Kaczynski's brother and sister-in-law recognized the writing and alerted the FBI. Agents arrested Kaczynski, a former mathematics professor, at his remote cabin near Lincoln, Montana, on April 3, 1996, and found bomb components, extensive journals and a live bomb.

A federal grand jury indicted Kaczynski in June 1996. On January 22, 1998, he pleaded guilty to all charges under an agreement that took the death penalty off the table, acknowledging responsibility for all sixteen attacks. On May 4, 1998, in Sacramento, U.S. District Judge Garland Burrell Jr. sentenced him to four life sentences plus 30 years without the possibility of parole, after victims and relatives of those killed addressed the court. Proceeds from a court-ordered auction of items seized from his cabin went toward restitution for the victims.

Kaczynski died in federal custody at the Federal Medical Center in Butner, North Carolina, on June 10, 2023, at age 81. Unabomber, a Netflix feature film about his early life and the FBI investigation, was released on September 25, 2026.