The alleged assault on the child is the latest in a series of brutal gender-related crimes that have caused outrage in India
Indian police are investigating the alleged rape of a three-year-old girl in her school in the city of Bangalore.
The child returned from school on Tuesday and complained of pain that had been caused by "an uncle in school", her parents told the police.
Police say they are questioning school staff and are waiting for a report on the child's medical condition.
The incident comes three months after a six-year-old was raped by a staff member in another Bangalore school.
That led to street protests by parents and activists, with many accusing the school of not handling the allegations properly.
"We have registered cases for rape and the Protection of Children from Sexual Offences (POCSO) Act," Bangalore Police Commissioner MN Reddi told BBC Hindi.
He said police were looking at security cameras for any leads. There have been no arrests yet.
The alleged assault on the three-year-old is the latest in a series of brutal gender-related crimes that have caused outrage in India.
Scrutiny of sexual violence has grown since the 2012 gang rape and murder of a 23-year-old student on a Delhi bus.
The crime sparked days of protests and forced the government to introduce tougher anti-rape laws, including the death penalty.
But the law appears to have failed to act as a deterrent. Statistics from the National Crime Records Bureau for 2013 show one rape was reported every 21 minutes.