Rajeshwari Karnan says that nine days after her son’s birth, his body caught on fire for no reason at all. Since then, he’s caught on fire three or four more times, making for a medical mystery that, if solved, could give doctors concrete answers about spontaneous human combustion (SHC).

"There was a flame on his belly and his right knee, and my husband rushed with a towel to put it off," Karnan told the New York Times. "I got very scared."

SHC is believed to occur when people catch on fire without an apparent source of ignition. In recent years, there have been quite a few deaths attributed to spontaneous combustion. In 2011, BBC reported that an Irish coroner ruled that a 76-year-old man who died in his home was the “first Irish case” of spontaneous combustion. And earlier this year, ABC News reported that spontaneous combustion was suspected in the death of an Oklahoma man whose charred remains were found in his kitchen.

In August 2012, research biologist Brian J. Ford theorized that SHC is caused by higher levels of acetone in the body in his article entitled “Big burn theory: Why humans spontaneously combust.” Ford experimented with acetone-infused meat and found that the meat burned and left behind “only fatty ash,” which is similar to what happens in the suspected cases of SHC.

“There have been a few cases where people have suffered SHC and have swatted the flames out, leading to their complete recovery,” said Ford. “In most examples it is fatal, as the cases are found after the event. Typically, there is just a pile of ash with protruding extremities.”

According to the New York Times, doctors in India investigated Karnan’s case, calling it a medical “dilemma.” The people in Karnan and her husband’s village forced the family to leave, fearing that the baby’s SHC would burn the village down.

“The parents have held that the child burned instantaneously without any provocation,” said Dr. Narayan Babu, of Kilpauk Medical Hospital. “We are carrying out numerous tests. We are not saying it is SHC until all investigations are complete.”

According to the Indian newspaper The Hindu, the baby was discharged from the hospital around noon Friday after being treated for extensive burn injuries. Doctors said there was no evidence to suggest that the baby did spontaneously combust.

"I still stand by what I said, that there is no such thing as spontaneous human combustion," said Dr. J. Jagan Mohan. "The possibility of child abuse exists and needs to be explored."