The men are reported to have taken a stranglehold on the girl and threatened her with, among other things, sexual violence.
It is said to have been five to seven masked youths. They are said to have taken an electric scooter that she was riding, her phone and pulled at her clothes. There are also reports that she saw a knife-like object, says Jennifer Last, press spokesperson for the Police Region West.
The teenage girl managed to get her phone back and get away from the scene. She is not believed to have suffered any more serious physical injuries.
The incident was initially investigated as an attempted rape, but was later changed during Tuesday to unlawful threats and sexual harassment as well as assault. There is still no suspect in the case.
The police are in great need of witness statements and urge people who have seen or heard anything to contact the authorities.