Test results on a baby who has "caught fire on his own four times" are expected this week.
Doctors in Indian are baffled about how and why 10-week-old Rahul went up in flames.
A native of a village near Tindivanam, Rahul has been undergoing treatment at Kilpauk Medical College and Hospital since Friday. He has caught fire four times since he was born, according to The Times of India.
The Times report says doctors are considering the possibility of spontaneous human combustion (SHC), a rare condition in which a person could catch fire due to the emission of highly inflammable substances through the body.
But burns specialist Dr J Jagan Mohan told The Times of India that SHC was a hoax theory.
"A baby catching fire spontaneously is not possible," Dr Mohan said. "Alcoholics have a very small percentage of alcohol secreted in their sweat but even that wouldn't generate a fire."
Doctors had recommended a series of sweat, urine and blood tests to check whether Rahul has inflammable substance in his samples.
"We're exploring all possibilities, including a case of abuse. The baby's organs are functioning normally and he is stable now," paediatrics chief Dr Narayana Babu said.
Most of Rahul's burn injuries have healed but he has scars on his head, hands, stomach and legs after he caught fire a month ago, according to The Times.
"The baby doesn't have any scars or burn injuries on his back. This could be because he was lying on his back and there was no air contact to cause a fire," he said.