Rupert Murdoch's News of the World hacked extensively into the voice mail of a minister in Britain's former Labour government, according to three people familiar with the matter.

The unauthorized access to voice mails left for Denis MacShane in 2004 and 2005, as he served as Minister for Europe, is one of a handful of cases to surface involving a serving government official in the phone hacking scandal that has engulfed Murdoch's News Corp.

A private detective hired by the weekly tabloid, which was closed by Murdoch in July as controversy over phone hacking allegation raged, hacked the voice mails left for MacShane, according to the three people familiar with documentary evidence held by British police.

MacShane remains a Member of Parliament, representing the city of Rotherham, South Yorkshire.

Some of MacShane's messages hacked by Glenn Mulcaire, a private detective who worked on retainer for the News of the World, included voice mails from Joan Smith, a newspaper columnist and crime novelist with whom MacShane had a personal relationship at the time, the evidence shows.

The people familiar with the evidence said that the News of the World's objective in hacking MacShane's and Smith's messages appeared to be to discover more information about their private relationship. However, the paper never published a story on the subject.

At one point, according to documents police seized from Mulcaire, the private eye wrote down details, apparently obtained from MacShane's voice mail, relating to a trip MacShane was about to take to Spain. The details included MacShane's flight number and arrival times, one of the sources said.

Another source familiar with the evidence said that Mulcaire's records included the home and mobile phone numbers of MacShane, Smith and MacShane's brother, and that the Spain trip information hacked by Mulcaire related to a confidential mission MacShane was making in his capacity as one of Prime Minister Tony Blair's principal advisors on Europe.

The idea that the (newspaper) could get into phones of a senior government official was worrying, this source said. An official familiar with British government security measures said that such phone hacking might have raised questions about security at Britain's Foreign Office, although it probably would not have been regarded as a major breach of national security.

MacShane and Smith declined requests to comment for this story. But Tamsin Allen, a lawyer with the London firm Bindmans LLP who represents MacShane, said police were in possession of phone-hacking notes made by Mulcaire about MacShane which contained information on MacShane and Smith. She said that MacShane had launched a hacking-related legal claim against the Murdoch organization.

A representative of News International, Murdoch's London-based newspaper company, said the company was not commenting on any individual cases. But this person said: News International continues to cooperate fully with the Metropolitan Police Service in its investigations. We are eager to assist it in any way possible to ensure that those responsible for criminal acts are brought to justice.

Sarah Webb, a lawyer for Mulcaire, declined to comment.

LEVESON INQUIRY

One of the sources familiar with the evidence of how Mulcaire hacked MacShane and Smith's messages said that the evidence strongly suggested that the hacking had been requested by a News of the World journalist other than Clive Goodman, a former Royal correspondent who was the first journalist at the tabloid to be implicated in phone hacking.

In 2007, Goodman and Mulcaire both were briefly jailed after they pleaded guilty to charges alleging that they hacked into the voice mail of aides to members of Britain's royal family.

Top Murdoch company executives in London said at the time that the hacking by Mulcaire and Goodman was an isolated occurrence. But evidence has surfaced recently that the practice was much more widespread.

MacShane is one of several dozen people who believe they were targets of media intrusion who have been granted status as core participants in a wide-ranging public inquiry into media reporting practices which was set up on the orders of Britain's current coalition government.

The inquiry, led by Lord Justice Brian Leveson, an English appeals court judge, is expected to begin hearing evidence in the next few weeks. Joan Smith has also been granted core participant status by the Leveson inquiry.

According to a person familiar with the inquiry, core participant status means that the inquiry will pay for a senior lawyer to advise and represent the participant at the inquiry. At some point the participant also will be granted access to evidence police collected during their phone-hacking related investigations.

People familiar with police inquiries related to phone hacking said that London's Metropolitan Police Service, also known as Scotland Yard, obtained much of the key evidence of alleged News of the World phone hacking years ago, at the time of Mulcaire and Goodman's initial arrest. But the evidence was not acted upon until police opened aggressive new inquiries into alleged media abuses earlier this year.

One of the issues the Leveson inquiry will examine is how Scotland Yard handled its investigations of phone hacking and other media practices over the years.

(Reporting by Mark Hosenball; Editing by Tim Dobbyn)