Former Turkish President Kenan Evren has died following several years of deteriorating health, the state-run Anatolia news agency reported Saturday. He was 98.

Evren was convicted last year for his role in a bloody 1980 coup. Agence France-Presse reported Evren had been undergoing treatment at the Gülhane Military Academy of Medicine in Ankara since 2012. Recently, he had been on a respirator.

Evren, a retired general and a former commander of the Turkish army, was one of two remaining members of the National Security Council that ruled Turkey following the Sept. 12, 1980, coup. He and former Turkish air force Gen. Tahsin Şahinkaya, 90, were sentenced to life imprisonment and demoted to private last June for dissolving Parliament, abolishing the constitution and ousting then-Prime Minister Süleyman Demirel. Both defendants had been too ill to attend the trial.

Daily Hurriyet said the Constitutional Court refused to overturn the convictions despite claims of rights violations. 

In 2010, voters overturned a constitutional clause that had granted general immunity to the coup leaders as part of Prime Minister Recep Tayyip Erdogan's effort to reduce the army's power, opening the way for a trial. Evren had threatened to commit suicide rather than let the trial go forward.

The coup has been labeled the bloodiest in Turkish history, killing hundreds. Sunday's Zaman said thousands were tortured in military and civilian prisons. Fifty people were executed and 500,000 arrested. Thousands were forced into exile. The BBC reported Evren justified the executions, saying: "Should we feed them in prison for years instead of hanging them?"

Coup leaders long said they had no choice but to intervene following years of chaos as a result of clashes between leftist and rightist forces.

“I do not regret what I did. I would stage a coup again under the circumstances of those times if I had the authority,” Evren said in 2011.

Evren was Turkey's seventh president, serving from 1983-89. After he retired, Evren took up painting. Two assassination plots against him were thwarted, the BBC said.