How the body creates fire
Spontaneous human combustion (SHC) occurs when a human body burns without an apparent external source of ignition.
Regarded by some scientists as a myth, the theory is that a person bursts into flames from a chemical or electrical reaction in body.
While there have been 200,000 reported cases in the past 350 years, not all have been thoroughly probed.
The first written account comes from Danish anatomist Thomas Bartholin in 1663, who described how a woman in Paris "went up in ashes and smoke" while sleeping.