A former Army general who headed Chile’s secret police in the late 1980s was sent to prison for life Tuesday for ordering the executions of 12 leftist guerrillas during the waning years of the Pinochet military dictatorship.

Retired Gen. Hugo Salas Wenzel had argued that he had no role in the June 15-16, 1987, killings known here as the Corpus Christi Massacre. The country’s Supreme Court, however, unanimously upheld a lower court conviction on the homicide charges as well as the court’s sentence of life.

Salas Wenzel, who had headed the country’s National Intelligence Center, became the first general to receive a life sentence in human rights prosecutions of former military leaders. The court also sentenced 14 others, including former Army Maj. Alvaro Corbalan, to shorter prison terms for their roles in the killings.