Scotland Yard was last night under intense pressure to reveal the names of politicians targeted by phone-hackers working for the tabloid press.
At least a dozen MPs, the majority of them Tories, are writing to the Metropolitan Police individually demanding to know whether their names are on the lists of people whose details were found when police raided the home of the private detective Glenn Mulcaire, who was working for the News of the World.
The latest development reflects growing frustration in Westminster at the failure of a police investigation started four years ago to produce any results beyond proving that the telephones of royal aides were hacked.
Among other developments yesterday it emerged that:
* The Home Affairs Select Committee will hold an inquiry into phone-hacking, as first reported in The Independent yesterday.
* The former News of the World employee Ross Hall, named by a previous MPs' inquiry as the man who transcribed swathes of hacked voicemail messages, said he will testify to police and the new parliamentary inquiry.
* The private investigator who was jailed planned to write a book alleging that phone-hacking was practised more widely at the News of the World.
* David Cameron's director of communications, Andy Coulson, will be interviewed by Scotland Yard over allegations of reporters phone-hacking when he was editor of the News of the World.
* MPs demanded that the Met Assistant Commissioner, John Yates, explain why the force did not warn politicians and celebrities it knew to be at risk that their voicemail may have been hacked.
* Mr Yates conceded that the Met's original phone-hacking inquiry, which led to only two people being jailed, could have been more thorough.
The police uncovered lists of thousands of private phone numbers and at least 91 pin numbers when they raided Mr Mulcaire's home – but only a small number of people have been informed by police that they were targeted.
Mr Coulson, who was editor of the News of the World at the time, is expected to be questioned by police about new allegations made by The New York Times, which suggest that phone-hacking was much more common than the newspaper has admitted and that Mr Coulson was personally implicated, which he denies. He has said that he will willingly co-operate with the police.
The News of the World has accused the US paper of being motivated by commercial rivalry, and senior Tories have accused Labour MPs of using the scandal as a political weapon to attack the Prime Minister by discrediting one of his closest advisers.
No Tory MP has publicly joined the clamour for a new investigation into the affair, though some are saying privately that Mr Coulson may have to resign if any more details emerge of phone-hacking that took place on his watch. Some also suspect that they may have been targeted by the newspaper during Mr Coulson's four-year editorship.
The Labour MP Chris Bryant wrote to all his fellow MPs yesterday advising them to contact Scotland Yard if they think they might be on one of the lists held by the police. Within three hours of sending out the message, he had received replies from a dozen MPs saying they were taking his advice – the majority of them Tory MPs, he said yesterday.
The former Scottish secretary Jim Murphy said yesterday that he has written to the Metropolitan Police Commissioner, Sir Paul Stephenson, as has Harriet Harman, Labour's acting leader.
Mr Bryant is seeking a High Court ruling to force Scotland Yard to reveal all the information they hold on him. He found out that his name was on the list of potential targets only after he wrote to the police to say that he suspected his telephone had been hacked by the News of the World. He believes they should have warned him straight away.
Mr Yates, appearing before the Home Affairs Committee yesterday, said that he would review the police's handling of Mr Bryant's case and speak to the MP personally.
He said that police will be speaking "in the near future" to Sean Hoare, a former News of the World journalist who told The New York Times that phone-hacking was a common practice and that Mr Coulson knew about it.
Mr Yates added: "I imagine we will be seeing Mr Coulson in some capacity."