Prosecutors announced Friday they would take no further action in Britain's mammoth phone-hacking probe, ending a four-year investigation that rocked the political and media establishment to the core. The Crown Prosecution Service (CPS) said it would take no further action against News Group Newspapers (NGN), global media baron Rupert Murdoch's British tabloid stable. England's state prosecutors also said there would be no further action against 10 journalists from the rival Mirror Group Newspapers (MGN) -- among them former Daily Mirror editor Piers Morgan.