Canadian police have launched an investigation to locate a teenage girl who went missing while attending the Toronto stop of the Vans Warped Tour on Friday (04Jul14).

Hannah Batty headed to The Flats at Molson Amphitheatres venue with friends, but she became separated from the group and was last seen at the lakefront concert at around 8pm local time, reports Billboard.com.

Authorities are now appealing to fans, bands, crewmembers and vendors for any information about the 15 year old, who had been sporting long blue hair, a Ghost Town T-shirt and cut-off denim shorts as she attended the rock gig.

They have asked people to check cell phones and cameras for any photos or videos she may have been inadvertently appeared in as bands such as Bayside, For Today, Bad Rabbits, The Color Morale and Get Scared rocked out on the venue's various stages.