MADISON, Wis. – Dwight Armstrong, one of four men who carried out a fatal bombing at the University of Wisconsin-Madison to protest the Vietnam War, has died. He was 58.

Armstrong, who spent years as one of the FBI’s most wanted fugitives after the 1970 blast, died Sunday at UW Hospital in Madison after battling lung cancer, hospital spokeswoman Susan Lampert Smith said. She said his family wanted the public to know he was a smoker because “they wouldn’t want anyone else to have to go through that.”

Armstrong was a shaggy-haired high school dropout when he and his older brother, Karl, and two others parked a stolen van packed with 2,000 pounds of ammonium nitrate and jet fuel next to Sterling Hall and lit the fuse on Aug. 24, 1970.

Enraged by the Vietnam War, the bombers said they were targeting the Army Math Research Center on the upper floors of the building. The bomb exploded in the middle of the night when they thought no one would be there.

But the blast killed Robert Fassnacht, a 33-year-old graduate student who was working overnight on a physics experiment. Three others were injured, and dozens of other campus buildings were damaged.

All four bombers are believed to have fled to Canada. Authorities pulled over their vehicle in Wisconsin shortly after the blast but released them. A vehicle carrying the Armstrongs was pulled over days later in New York, but again they were let go.

Dwight Armstrong lived underground but was eventually arrested in Toronto in 1977. He had been arrested in San Diego for theft while living under an assumed name the prior year but released before the FBI could learn of his true identity.

Bombers Karl Armstrong and David Fine had already been captured, convicted and sentenced to prison. The fourth, Leo Burt, disappeared and his whereabouts remain unknown nearly 40 years later.

Madison attorney Lester Pines, who was part of Armstrong’s defense team, recalls flying to Toronto to help negotiate his extradition and plea agreement. Armstrong was sentenced to seven years in federal prison and was among the last people imprisoned in the U.S. for Vietnam-era protest activities.

Armstrong later expressed remorse for killing Fassnacht, but said the bombing was well intentioned.