DUBAI (Reuters) - Saudi Arabia s Attorney General said on Monday detailed questioning of individuals detained on the back of an anti-corruption probe had taken place and  a great deal of evidence  had already been gathered.  Dozens of people including royals, ministers and businessmen have been detained in an investigation by a new anti-corruption body headed by Crown Prince Mohammed bin Salman.  Yesterday does not represent the start, but the completion of Phase One of our anti-corruption push,  a statement by Attorney General Sheikh Saud Al Mojeb said.  The investigations were done in a discreet manner, the statement said,  in order to preserve the integrity of the legal proceedings and ensure there was no flight from justice.  