Savage kidnapping leaves mother dead and child in coma

A crime scene has been set up where a burnt-out car and woman's body were found in Sydney. (Steven Saphore/AAP PHOTOS)

A mum is dead and her eight-year-old son is in a coma after a shocking kidnapping which may have ended with her being burnt alive.

A group of up to five men broke into the 45-year-old woman's Bankstown home, in Sydney's southwest about 10.30pm on Thursday and severely assaulted both her and her son, before she was dragged into an SUV.