Teen assaulted by Sydney train stalker

A 15-year-old girl has been indecently assaulted by a man who followed her on a train in Sydney's south.

The man, described as being of Asian appearance with a Canadian accent, first spoke to the girl as she waited for a train at Hurstville Railway Station on Monday afternoon and followed her when she got off at Wolli Creek, police say.

It's alleged the man allegedly assaulted the teenager at nearby Discovery Park.

Police have released CCTV footage of the man who's believed to be about 30-years-old and are urging anyone with information to contact them.