Police are appealing to the public for any information of a vulnerable missing man from Aylesbury.
Mr Wheeler is 5ft 9ins tall, of stocky build, with short brown hair and brown eyes.
He was last seen in the Bierton Road area where he was wearing grey tracksuit trousers, a grey t-shirt, jacket and sand-coloured boots.
More top news
Tuesday night's weather for the west of the region
Tuesday night's weather for the east of the region
Tuesday afternoon's weather for the west of the region