The 49-year-old was last seen this morning (Monday 12th November) and was reported missing to the Police later in the day.
His disappearance is described as out of character.
Police are tonight searching Parkhurst Forest with the assistance of WightSAR, as first reported by Island Echo. The Police helicopter is also understood to now be airborne over the area.
Mark is described as white, around 5ft 6ins tall, of very small build with brown, thinning hair. He was last seen wearing black boots, black trousers and a black woolly hat and is possibly wearing a fluorescent orange jacket.
Family members say he is most likely wearing glasses and it is believed he is carrying a small blue and black rucksack.
If anyone has seen Mark, call Police on 101, quoting reference number 745 of 12/11/18.
UPDATE TUESDAY @ 07:13 – Mark has been found safe and well this morning, Police have confirmed.