Parents of a four-year-old girl studying in a reputed school in Maharashtra's Thane city have alleged that an unidentified person sexually assaulted her, prompting police to launch an investigation, officials said, reported news agency PTI.

In their complaint to police, the parents have alleged a person in blue clothes sexually assaulted their daughter in the school premises on July 30 between 11.15 am and 3 pm, the officials said on Monday, reported PTI.

Taking serious note of the matter, the police examined the CCTV footage of the school as part of their probe.