A South African man has been convicted by the Nelspruit Regional Court, for allegedly raping his 77-year-old mother who is both disabled and mentally challenged, reports Times Live.

The 41-year-old man from Thembelinhle Trust outside White River, Mpumalanga, pleaded guilty to the charge of rape in the incident that happened on June 19, 2015 after his relatives reported to the police that he raped his biological mother at her home.

A statement by his lawyer, Nhlanhla Malumane, reads:

“I hereby plead guilty without undue influence. I know the victim in this matter. She is my biological mother who is mentally ill and disabled.

I returned from work and found her sitting on the bed in her room. I did, with force, rape her. I know that my action is unlawful and is punishable by law.”

Magistrate Vanessa Joubert found him guilty and postponed the case to January 27 for a pre-sentencing report from social workers.

State prosecutor Cindy Sihlongonyane said according to a psychiatric report, the victim is unable to speak or understand anything.