Mumbai: A four-year-old girl was raped by a school supervisor, triggering protests by a group of people which vandalised the private institute's property here, police said yesterday.

The junior KG student was sexually assaulted by the accused, Kesari Upadhyay, who worked as a supervisor at the private school, in a toilet on December 9, the police said, adding he was arrested today.

Earlier in the day, a group of people protested against the incident outside the school in suburban Bhandup before barging inside and damaging its property, they said.

The girl lives with her mother and maternal grandparents. Her father had been missing for the past few years, Bhandup police said.

The victim narrated the incident to her grandmother who initially did not take her seriously. Eventually, the minor's family lodged a complaint and the girl's statement was recorded last night, they said.

Based on her statement, an FIR was registered against Upadhyay under relevant sections of IPC and the Protection of Children from Sexual Offences (POCSO) Act, and he was apprehended, the police added.