NJ mom Chevonne Thomas seen topless, upset, before son was decapitated

Cadavers help police solve crimes? Absolutely. At the University of Tennessee's Forensic Anthropology Center, a.k.a. the Body Farm, cadavers are left to rot under various environmental conditions so scientists can learn just how bodies decompose - and how long it takes them to decompose. Forensic scientists use the data to better locate and recover human remains - and solve crimes.
A police officer talks to residents of Camden, N.J., where police say a New Jersey mother decapitated her 2-year-old son before fatally stabbing herself, Wednesday, Aug. 22, 2012.
AP Photo/Mel Evans

(CBS/AP) CAMDEN, N.J. - A New Jersey woman who apparently decapitated her 2-year-old boy before killing herself was seen sitting on her front steps a short time earlier, topless and upset.

Neighbor Melanie Troutman says she saw 33-year-old Chevonne Thomas sitting with her boyfriend in front of their Camden home about 10:30 p.m. Tuesday. Troutman tells The Associated Press that the woman was "clearly upset."

She says the boyfriend led Thomas back into the home a short time later.

Police say Thomas apparently decapitated Zahree Thomas and put his head in the freezer before calling 911 just after midnight Tuesday to report something had happened to her child.

Court records show Thomas faced dozens of judgements and liens filed in civil court in New Jersey dating back to 2002.

Authorities say Thomas had regained custody of her son just five months ago. Prosecutors say she lost custody in 2010 when she allegedly left the boy unattended in a car. At the time authorities say she admitted to having smoked marijuana laced with PCP and blacking out in a park.

More on CrimesiderAugust 22, 2012 - Mother, toddler dead in NJ decapitation-suicide, police say