Police are appealing for public assistance to help locate missing Oak Park man Alexander.
The 21-year-old was last seen boarding the 3.34pm Upfield line train from platform 3 at Melbourne Central Railway Station.
Police and family hold concerns for his welfare as he has down syndrome and is very shy and would be unlikely to ask for help or assistance.
He was last seen wearing a grey coloured hoodie, dark coloured pants and was carrying a green backpack with a single shoulder strap.
Police have released images of Alexander in the hope someone recognises him and can provide information on his current whereabouts.
Anyone who sees Alexander is urged to contact Melbourne East Police Station 9637 1100.