Image caption Daniel Morgan was murdered in 1987 but no one has ever been found guilty

An MP who has spoken out against phone hacking is calling for the murder of a private investigator to be examined as part of the inquiry into the scandal.

Tom Watson believes the News of the World's links to private investigators could shed new light on the unsolved killing of Daniel Morgan in 1987.

Mr Morgan, 37, was found with an axe in his head in south London.

Until his death he worked with Jonathan Rees, whose company has been linked to alleged email hacking.

Mr Rees was one of five men accused of murdering Mr Morgan in 2008, but after almost two years of legal wrangling, the trial collapsed in March when "supergrass" evidence was deemed to be unreliable.

Now Mr Watson is keen to explore the connections between Mr Rees and Alex Marunchak, who was the News of the World's crime editor in the late 1980s, and who later became the paper's Ireland editor.

He says he has seen evidence that the two men stayed in contact even when Mr Rees was sent to prison for conspiracy to pervert the course of justice in 2000.

BBC Radio 4's Report programme has also seen evidence suggesting that a week before Daniel Morgan died, he said he was taking a story exposing police corruption to Mr Marunchak, and was promised a payment of £40,000.

In a letter Alex Marunchak's lawyers told the BBC: "Our client has never had any contact with Daniel Morgan and denies all allegations of wrongdoing."

However, Mr Watson wants all relevant information and evidence to be taken into account as part of the judicial inquiry into wrong doing by the media.

He told The Report he would write to the prime minister to ask for Daniel Morgan's case to be scrutinised by Lord Leveson's inquiry into phone hacking.

Daniel's brother Alastair Morgan, who is calling for a separate judicial inquiry into the case welcomed the move:

"It's really heartening to hear that somebody is taking this seriously," he said.

"For years and years our concerns were dismissed."

Jonathan Rees has stated he did not commission, or in any way incite or procure anyone to "hack" any computer.

The Report is on BBC Radio 4 on on Thursday 18 August at 20:00 BST. Listen via the BBC iPlayer or download the programme podcast.