"I will never forgive myself for what I did to that lady. There is no excuse for what I did, I take full responsibility. I am totally ashamed," Dias told the Manchester Evening News.
"Until that night I had worked with the lady for many months. I liked her, she was a real character."
He says he has apologised to the family but his apology has not been accepted.
The woman's daughter called the men "evil and a disgrace".