A girl of around 18 years who was allegedly sexually assaulted at a sugarcane field by one of her relatives committed suicide by hanging herself from ceiling fan at her residence on Monday. No suicide note was received from the house, said police. She along with her parents had registered a complaint at laksar police station on October 21. A laksar police station officer said that a case under 306 of IPC was registered against the accused following which he was arrested.