Woman with knife threatens boy on Vic tram

A woman held a knife to the neck of a 14-year-old boy and demanded his phone on a Melbourne tram.

Police released images of the woman who tried to rob the boy on the 86 tram when it was stopped on Plenty Rd in Preston just before 4pm on June 11.

The woman, aged 20 to 30 and with long brown hair, left empty-handed and fled towards Bell St on foot.