Gregorio 'El Goyo' Alvarez, Uruguay's ex-military ruler, dies in prison at 91

MONTEVIDEO, Uruguay, Dec. 29 (UPI) -- Gregorio "El Goyo" Alvarez, Uruguay's former military leader serving a 25-year sentence for murder and human rights violations, has died in prison at the age of 91.

Alvarez, who ruled as de facto president from 1981-85 following years of military rule stemming from a 1973 coup d'etat, died from heart failure on Wednesday in a Montevideo prison after a hypotension incident, LaRed21 reported.

In 2007, Alvarez, who served as commander-in-chief of Uruguay's national army from 1978-79, was arrested on charges of kidnapping Uruguayan political activists living in exile in Argentina.

Prosecutors said exiles were taken from Argentina back to Uruguay, where they disappeared under Alvarez's rule. In 2009, Alvarez was found guilty of killing 37 of those exiled during his terms as head of the army and the country's de facto president.

Military rule in Uruguay ended in 1985. Alvarez continued to live in Montevideo after his resignation as he was partly shielded by a 1986 law that required judges to consult Uruguay's executive branch before opening cases related to war crimes under military rule. Alvarez was arrested after repeated protests led by the families of missing exiles.