Vikhroli police said neighbours in Tagore Nagar heard the girl screaming, rushed out and saw her aflame. The girl was alone at home and they rushed her to Rajawadi hospital.
Doctors at the hospital said that the girl suffered 90 percent burns.
According to initial information, the girl's parents had gone to meet a doctor about her ongoing treatment for epilepsy. The parents have acknowledged that she has tried to harm herself in the past, so the police do not suspect foul play.
"The girl has been under treatment for her ailment over the past three years. This is not the first time that she has tried to hurt herself, but this time it is very serious," said SL Sarkkte, assistant police sub-inspector.