He was last seen wearing black shorts, a black top with a Hindu symbol on the front, Adidas trainers with white stripes and was carrying a black rucksack. He was also riding a green BMX bike.
He is possibly in possession of an Oyster card.
Mr Marsh added: “Omar we love you and you are not in any trouble all. There is no pressure on you we just want you to be safe.”
Anyone with any information as to Omar's whereabouts is urged to contact police on 101 quoting ref 16MIS031563