A female victim reported that she was on a Fremont bound train when a male suspect (BM, 19-25, grey hoodie, who was with about 4-5 other juveniles, BMs teens-20s) approached her and demanded her belongings. He then showed what appeared to be a black semi-automatic handgun in his waistband before taking her cell phone and wallet. He and his companions off boarded the train at the Coliseum Station and were not located by responding officers. Video is being requested from the train and the Coliseum Station. The victim was not injured. The victim did not have tracking enabled on the phone.