David Cameron has unveiled the final terms of reference of Lord Justice Leveson's inquiry into phone hacking, announcing his remit will extend beyond newspapers to include broadcasters and social media.

The prime minister also named the panel of six people who will work with the judge on the inquiry.

They are the former political editor of Channel 4 News, Elinor Goodman, the former political editor of the Daily Telegraph, George Jones, the former Ofcom director David Currie, Liberty director Shami Chakrabarti, Sir David Bell, the former chairman of the Financial Times, and Sir Paul Scott-Lee, a former police chief.

Charkabarti said it was a "daunting privilege" to be invited on participate in such an important public inquiry.

Cameron said the inquiry had also been widened to cover other police forces beyond the Met.

"The inquiry should consider not just the relationship between the press, police and politicians but their individual conduct too," he told the Commons, opening a debate on the phone-hacking scandal for which the parliamentary session was extended by a day.

He said some significant amendments had been made to the remit of the inquiry, which will "not just consider the relations between the press, police and politicians, but their individual conduct too".

Cameron said the "torrent of revelations and allegations" over the past two weeks had "engulfed some of this country's most important institutions" and "shaken people's trust" in the media, police and politicians and media owners.

Broadcasters and social media will be included in the inquiry where there is "any evidence of criminal activity".

The BBC said it would not comment at this stage.

A spokeswoman for ITN said it had noted the prime minister's announcement and would cooperate fully.

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