Ted Kaczynski, the man known as the Unabomber who carried out a 17-year bombing campaign that killed three people and injured 23 others, died by suicide. Four people familiar with the matter confirmed the cause of death to The Associated Press but were not authorized to discuss it publicly. The 81-year-old Kaczynski was found unresponsive in his cell at the Federal Medical Center in Butner, North Carolina around 12:30 a.m. on Saturday. Emergency responders performed CPR and revived him before he was transported to a hospital. He was pronounced dead later Saturday morning. Kaczynski was suffering from late-stage cancer. Kaczynski lived as a recluse in rural Montana, where he carried out a solitary bombing spree that changed the way Americans mailed packages and boarded airplanes.