A 41-year-old woman is behind bars awaiting extradition to Michigan after she allegedly murdered her 9-year-old son and buried him in a shallow grave before fleeing the state with her other son.

The case began on Jan. 6 when Detroit police were called to a home in the 19700 block of Woodingham after a landlord discovered a shallow grave in the backyard.

“Upon arrival, the police were shown that grave where a human foot was sticking out of the ground,” Wayne County Prosecutor Kym L. Worthy told reporters.

His hands and feet were also bound, she said.

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Cops identified the boy as 9-year-old Zamar King III. Detectives later determined that his mother, Brandee Katrice Pierce, 41, murdered him on Oct. 24. The medical examiner in Michigan ruled the child’s death as being caused by smothering and compression to the neck, police said. About two weeks after the murder, Pierce fled the Mitten State and moved to Georgia where she was arrested on unrelated charges on Dec. 20.

The Detroit Free Press obtained a police report from the December arrest that said a concerned citizen called police in Brookhaven, an Atlanta suburb, after seeing a 3-year-old boy alone in a car. Cops responded and recovered the boy, who was cold to the touch (temperatures were in the 40s that day) but was otherwise unharmed. Officers noticed there was human feces in the backseat along with a deflated air mattress, the complaint reportedly said. Pierce said she and the boy had been living in the car and she donated plasma to make money. She was arrested for second-degree child cruelty and the boy was placed in foster care.