He was last seen at his home address at about 9.30pm on Wednesday, December 14.
Martin is described as white, 5’8″, with blond hair and green eyes.
He was last seen wearing a black Canada Goose jacket, black North Face trousers, black Nike trainers and possibly a black hat.
Anyone who sees him or knows his whereabouts is asked to report it to Sussex Police online or call 101 and quote serial 65 of 15/12.
