The names emerged as British police, initially investigating the suspected interception of phone messages intended for Prince William, widened their investigation to take in dozens of high-profile public figures who have fallen victim to the practice known as "phone screwing".

Clive Goodman, the News of the Wo r ld 's royal editor, is due to appear in court on Wednesday charged with a string of offences relating to intercepted voicemail messages.

Former footballer Glen Mulcaire, who now runs a "crisis management consultancy", was also charged.

The News of the World attempted to damp down the controversy on Friday, announcing that Goodman had been suspended pending the outcome of the court case. The move is unlikely to spare the newspaper further negative headlines or police investigation.

In some respects, Goodman can be considered unlucky. According to media sources, phone hacking has long been common practice throughout Fleet Street, and hundreds of tabloid journalists may yet be caught up in the investigation.

Detectives launched the probe after members of Prince Charles' staff reported a possible security breach, but one former tabloid editor said the investigation has already spread far beyond its initial focus.

"Dozens of recent exclusives come from illegal tapping. I understand there are 250 other journalists involved in this investigation, " he said.

Senior News of the World editorial executives may also face questioning, and anti-terrorist police leading the investigation may seek a warrant to search the newspaper's records for details of payments to the alleged phone tappers, according to the Press Gazette.

Numerous tabloid scoops are believed to have originated with or been confirmed by illegally accessed phone messages.

Former Home Secretary David Blunkett became concerned that his phone was tapped following the News of the World's reports of affairs with Kimberly Fortier.

TV presenter John Leslie discovered that his voicemail had been accessed by reporters during media revelations concerning his chaotic personal life, said James Herring of Taylor Herring PR.

"When he was in the middle of the media storm he found he couldn't access messages. At the time he thought his phone had had a meltdown under the pressure of all the calls, but a journalist had actually gone into the phone and changed the settings so that only he could access messages, " he said.

"We advise clients that if they need to have an important conversation, do not have it on the mobile.

You're better off having a conversation one to one, " he said.

Media sources have said tapped voicemails also led to the revelation of Keira Knightley's relationship with actor Rupert Friend. Knightley's agent Lindy King said she was not aware that her client had been targeted.

One former tabloid journalist said yesterday that it was "routine" to hack into mobile phone voicemail systems, especially to confirm 'kiss and tell' stories.

"It used to happen all the time.

I'm only surprised that the mobile phone companies have not cottoned on to this, " he said.