Police have welfare concerns for 18-year-old Maitland, who was last seen in Redcliffe, around 3.40pm, Thursday, October 21.
Maitland is described as being 177cm tall with dark skin, dark hair and a heavy build.
He was last seen wearing long green trench coat, dark blue cowboy hat, black long sleeve top, sneakers with black socks.
Maitland is autistic and enjoys using public transport.
Some online comments have suggested he may have travelled on the Mandurah train line, but this is unable to be confirmed by police at this time.
Anyone who sees Maitland is asked to call police immediately on 131 444 and quote CAD 795683.
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