PORTSMOUTH (AP) — A southern Ohio woman was convicted Thursday of rape, kidnapping and other charges related to her grandchildren and was immediately sentenced to four life prison terms with no chance for parole.

A jury in Scioto County deliberated for nearly six hours before convicting the 53-year-old woman. She testified the day before that the children were lying about being chained, beaten, underfed and sexually assaulted.

The case in the Ohio River town of Wheelersburg arose after one girl emailed a teacher for help. The children’s mother and her boyfriend previously pleaded guilty to rape charges and were sentenced to prison last week.

A prosecutor depicted the grandmother as a guardian who didn’t speak up about the abuse because she didn’t want to lose hundreds of dollars in government benefits paid for the three children.

“I have seen a lot of evil but this is the most evil I have ever seen,” Judge William T. Marshall told the woman, according to the Portsmouth Daily Times. “You have shown no remorse. You put those children through hell.”

The Associated Press is not naming the adults to protect the children’s identities.

During her testimony, the grandmother acknowledged she punished the children with spankings and by making them face a wall but denied hurting them further, explaining that the chains in the house were for a dog and the children’s bruises and scars were from playing “cops and robbers” with ropes.

But she conceded regrets.

“I failed my grandchildren,” she said, according to The Columbus Dispatch. “I should have done more. I beat myself up for that every day. I’m sorry.”