A mother who was "overwhelmed" by the responsibility of taking care of her developmentally disabled daughter killed her in their home. Sandra Speck, 50, is facing murder charges in the death of her daughter, Mindy Speck, 21, in Ohio, the Associated Press reported Wednesday.

Prosecutors have not released details about the alleged murder, so it's unclear how Mindy Speck died. An autopsy could take several months to be completed.

The family lived together at their apartment in Eastlake, 20 miles east of Cleveland. Then last week, Sandra Speck walked into a local police station and confessed to killing her daughter.

Sandra Speck later pleaded not guilty to the killing. She remains jailed on a $50,000 bond after appearing in court Tuesday.

Eastlake Prosecutor Judd Hawkins said Wednesday Sandra Speck was “overwhelmed” by her daughter's special needs and had problems restraining her. 

"It's a tragedy for the young woman who lost her life, it's a tragedy for her mother, and it's a tragedy for the family," Hawkins said.

Lake County Public Defender Charles Grieshammer said in court Tuesday that Sandra Speck devoted her life to her daughter's and called it a “difficult situation.”

"Her daughter was the love of her life," Grieshammer told reporters after the hearing. "She cared for her tremendously."

Grieshammer said Sandra Speck was "feeling horrible" about her daughter's death.

Sandra Speck did not a criminal history before the killing, police said.

Parents killing their disabeled children is not unheard of. In May, an Illinois mother was sentenced to four years in prison for drugging and killing her disabled 28-year-old daughter in a failed murder-suicide, CNN reported. In Georgia, an Augusta mother was convicted of murder in June for killing her profoundly disabled adult son who was completely dependent on her for care.