BUCHAREST, Romania (AP) — Romanian authorities say Alexandru Visinescu, a communist-era prison guard serving a 20-year sentence for crimes against humanity, has died in prison at 93.

Bianca Filote, spokeswoman for the Institute for Investigating the Crimes of Communism told The Associated Press that Visinescu died Monday at Rahova prison hospital.

He was convicted in 2015 for the abuse and killing of prisoners at Ramnicu Sarat prison in eastern Romania during his command from 1956 to 1963. He was imprisoned in February 2016 after losing his appeal.

Former prisoners testified they were denied access to medical treatment, heating, exercise and adequate food. They were held in solitary confinement and beatings were common.

Visinescu claimed he was merely following orders.

The lockup housed members of Romania's intellectual, political and military elite prior to the communist era.