Police inspector B G Karkar of Thane's Kalwa police station said that the victim was playing outside the courtyard of the house, when she was lured and taken behind a temple and molested after gagging her mouth on Thursday afternoon.
The little girl was also threatened with dire consequences if she raised an alarm.
The child went straight to her parents and narrated the incident, after which her family registered an offence at the police station against the unknown accused who is absconding.
Offences under Section 376 (2) of the Indian Penal Code and Section 4 of the Prevention of Sexual Harassment of Children Act of 2012 have also been registered against the absconder, the police said.