Jorge Rafael Videla, the former dictator of Argentina, has died at the age of 87.

According to an Associated Press report, Videla died in the Marcos Paz prison in Argintina. He was found dead in his prison bed early Friday morning, and the cause of death has been reported to be natural causes.

Videla was sentenced to life in prison in 1985 for his part in the human rights violations perpetrated by his government. Videla led a military coup in 1976, shortly after the death of Argentine leader Juan Perón. He established a military government that killed thousands of Argentinians during the so-called ‘Dirty War,’ a civil war between the government and guerrilla left-wing groups in the country. The government is remembered for not only killing Marxist fighters, but also ‘disappearing’ thousands of students, left-wing political activists, and other dissidents.

Videla ceded leadership in 1981, shortly before the military government fell. At his trial in the 80s, Videla was found guilty of charges that included murder, kidnapping, and torture. Videla served five years in prison before being pardonded by Argentine President Carlos Menem in 1990. He returned to prison in 1998 on charges of kidnapping children, though he served under house arrest due to his age. His presidential pardon was thrown out in 2007, and he returned to prison after another trial.