A multi-million dollar collection of Andy Warhol silk screen portraits has been stolen from a Beverley Hills home in Los Angeles.The ten works feature sporting super stars of the 1970s. Police think the thieves will have difficulty selling them on. ‘‘Artworks of this significance are very hard to move and so, I believe, just based on past experience, these will surface. At some point they will show up. It is just a question of whether it is sooner or later,’‘ said Detective Don Hyrcyk from Los Angeles Police Department. Portraits of boxing great Muhammad Ali, football star Pele, figure skater Dorothy Hamill and trial of the century defendant OJ Simpson were among the pictures taken. A reward of one million US dollars, about 700,000 euros, has been offered for information leading to the return of the artwork.