CAMDEN, N.J. – The 911 call from Chevonne Thomas was rambling and incoherent, but authorities said she made one thing clear: Her 2-year-old son had been stabbed, and “I did it.”

What police found at her Camden rowhouse early Wednesday was even more horrifying. Thomas had decapitated her son and placed his head in the freezer.

The 33-year-old mother later fatally stabbed herself after hanging up on emergency dispatchers, a violent end to a troubled life.

Some neighbors described strange behavior by Thomas, who had just moved to the street from elsewhere in the city. Others saw no evidence of problems.

“Because, had we known something was up, I’m quite sure all the neighbors on this block would have talked to her,” said Tayari Horcey, who lives a few doors from Thomas. “But, you know, people hold stuff in. You don’t know what’s going on.”

The state’s child welfare agency said in a statement that Thomas had been receiving counseling and support services since a court-ordered reunification with her son April 3.

She previously lost custody of Zahree to relatives after allegedly leaving the boy unattended in a car, telling police she had smoked marijuana laced with the hallucinogenic drug PCP and blacked out in a nearby park. She was ordered to undergo treatment for substance abuse and mental health disorders, according to the Department of Children and Families.

Thomas was charged with child endangerment in the 2010 car incident, but the case was dropped because of a problem with a witness, said Jason Laughlin, spokesman for the Camden County prosecutor’s office.

Thomas called 911 late Tuesday about two hours after neighbors say she had been sitting on her front steps “clearly upset.” During the call, she first accused her boyfriend of stabbing Zahree, but then quickly recanted.

“You know what, I did it, I’m lying, I’m lying, I’m lying, I did it,” she said, according to a recording of the rambling, often incoherent call released Wednesday evening.

When asked if she takes medicine, Thomas said she used to take the antidepressant Prozac.

“I didn’t take it today, but I should have,” she said.

Police later found Zahree’s body on the first floor of his mother’s home, then discovered his head in the freezer. A medical examiner found a chest stab wound and marks on the child’s arms, Laughlin said.

Thomas stabbed herself in the neck with a kitchen knife shortly after hanging up on dispatchers, he said.