It's been six months since Toronto teen Mariam Makhniashvili was last seen and detectives say they still don't have any leads on her disappearance.

The 17-year-old girl was last seen by her brother on the morning of September 14. The two walked to Forest Hill Collegiate together but went into the midtown Toronto school using two separate entrances.

The girl never made it to class.

Weeks after, police found Mariam's backpack in a busy alleyway near Mt. Pleasant Road and Eglinton Avenue. That was the last solid clue police uncovered in the case.

The Makhniashvilis moved to Toronto in June 2009. Mariam and her brother George immigrated from the Republic of Georgia. They joined their parents who moved to Toronto after a brief stint in Los Angeles for work.

Mariam, who has been described as a quiet, shy girl, had made few friends at her new school. No one at Forest Hill Collegiate remembered seeing or speaking to the girl.

Each student at the school was questioned by a team of police officers. Investigators also knocked on every door in the immediate area to speak with local residents but police say they still have no leads in the case.