Perth man tipped from wheelchair and robbed

A wheelchair-bound man has been tipped onto the ground and robbed at knifepoint in Perth after he was confronted by a man asking for a cigarette.

The victim, in his 50s, had his wallet and keys stolen as he lay on the ground - where he remained until police arrived - in East Victoria Park on Sunday night.

Police are looking for a fair-skinned, tall and skinny man in his 20s or 30s who was riding a blue mountain bike with a brown milk crate on the back.