A woman who killed her toddler daughter has claimed that she committed the murder on the instructions of the animated character SpongeBob SquarePants.

Justine Johnson, 22, has been charged with felony murder and first-degree child abuse in connection with the death of her three-year-old daughter, Sutton Mosser, on September 16 last year. The victim was found dead by her uncle and Johnson's brother, Knesley Johnson, the next morning at her grandmother Alisa Johnson's home. Alisa said she had asked Justine to stay at her house instead of her own apartment so Knesley could help her take care of the baby.

Justine's teenage brother also stayed with them, and had witnessed her doing cocaine on the day of the crime. She was allegedly going through heroin withdrawal at the time.

Knesley started looking for his sister after he couldn't find her upon returning from work, and ultimately spotted a human foot sticking out of a black garbage bag. He alerted the police who confirmed that the body belonged to his niece, who according to her autopsy died of multiple stab wounds.

The police also conducted a search of the accused's old apartment and found blood on the floor and in a bathtub, but have not been able to ascertain whose blood it was. The cops located her soon after, walking along a railroad track. She initially refused to answer questions by detectives but was arrested later that day.

She has been in prison without bond since September last year, but is pleading not guilty to the charges. According to a report on CNN, the accused also told an official from Iosco County Child Protective Services that she heard a voice from her television threatening her life and saying she would die if she did not murder her daughter. She allegedly said that the voice belonged to SpongeBob SquarePants, the title character of the iconic Nickelodeon cartoon.

A judge determined last month that Johnson was mentally fit to stand trial. Meanwhile, the accused's mother Alisa claimed in her defence, "My daughter loved her child" and "the people are portraying her as someone she is not."

SpongeBob SquarePants
SpongeBob SquarePants. Larry French/Getty Images for A E Networks