An Amber Alert has been issued in Calgary, Alberta for a missing five-year-old boy and his grandparents.

5 year old Nathan O Brien has blond curly hair and blue eyes and was wearing peach coloured shorts and a striped blue hoodie.

Alvin Liknes, 66, has grey-blond hair and Kathryn Liknes, 53, has red-brown hair and green eyes. Alvin walks with a slight limp. Both are considered missing. Calgary police continue their investigation. Anyone with any information should contact Calgary Police or Crime Stoppers.