Media playback is unsupported on your device Media caption Iain Packer: "I've not been rough with any woman. I've never hurt a woman in my life."

A man questioned by police over one of Scotland's most high-profile murders has spoken publicly for the first time.

Iain Packer was interviewed by police investigating the death of sex worker Emma Caldwell whose body was found in a Lanarkshire forest 14 years ago.

BBC's Disclosure asked Mr Packer if he had taken Ms Caldwell to the woods for sex. He said he made that admission to police, but it was done under duress.

He insists he had not been there before and did not kill the 27-year-old.

Police Scotland said that to protect any potential legal case they were limited in what information could be released.

In May 2005 Ms Caldwell's body was found in isolated woods near Roberton. She was naked and had been strangled.

The woods are 38 miles from Glasgow's red light district where she would normally sell sex.

Image caption Emma Caldwell's body was found in a wooded area more than 30 miles from Glasgow

In an interview for a documentary, "Disclosure: Who Killed Emma?", Mr Packer insisted he did not see her on the night she went missing.

Ms Caldwell's body was found five weeks after she was last seen, and police interviewed hundreds of men identified as regular users of sex workers.

Mr Packer, from Glasgow, was one of those men.

A sex worker told police that Ms Caldwell said he was obsessed with her.

Mr Packer gave six statements to police between 2005 and 2007, but was not interviewed under caution as a suspect.

Initially, the 46-year-old told detectives he did not use prostitutes and had never met Ms Caldwell.

Remote woodland

However, in later interviews, he said to police he had in fact paid her for sex more than a dozen times.

During those police interviews Mr Packer also made a series of admissions.

He told detectives that not only had he paid Ms Caldwell for sex, but that he also took her, and several other sex workers, to the remote woodland where the body was found.

Image copyright David Gillanders Image caption The woods near Roberton, where Emma Caldwell's body was found, are more than 30 miles south of Glasgow

When asked about the admissions he made to police, Mr Packer told the BBC: "In that room that day, you're bombarded with questions, calling you a liar. You start to question yourself.

"If you're sitting in a room with two guys point blank, hounding you for hours, restricting you where you go for a fag, restricting you when you go to the toilet, restricting you the fact that they won't give you a lawyer, it's bully tactics is the way I'd put it."

He told officers that Ms Caldwell was the first sex worker he had taken to the woods, and that he took her there six times.

And in March 2007, he took two policemen down to the area where her body was found.

But in his interview with Disclosure he insisted that officers led him there rather than the other way around.

He said: "I couldn't even tell you how to get there.

"First time I've ever been there."

The BBC understands that when Mr Packer went to the woods with detectives, they asked their superiors whether he could be charged, and the response was to let him go.

At the time, the police investigation was focused on four Turkish men, who were charged with Ms Caldwell's murder in August 2007.

However, within a year, the case had collapsed and the men were released.

Concerns over the case were such that in 2015 the Lord Advocate ordered Police Scotland to re-investigate not only who killed Ms Caldwell, but also what went wrong in the original murder inquiry.

Mr Packer said the police have not spoken to him about the matter since his last interview in 2007.

Image copyright PA Image caption The last picture of Emma Caldwell before she was found dead in woodland 14 years ago

The documentary also heard allegations of rape against him.

One involved Ms Caldwell. A former detective told the programme that he took a statement alleging that Mr Packer had raped Ms Caldwell behind billboards in Glasgow's east end, months before she was killed.

Mr Packer steadfastly denied that he had raped her.

He told the BBC: "Could it have happened to her? Yeah, possibly. But it wasn't me."

The documentary also features Magdalene Robertson, whose relative was in a relationship with Mr Packer in the 1990s. Ms Robertson said she was 15 and living in Glasgow when he attacked her.

"One night I woke up and he was sitting on the edge of my bed, staring at me," she said. "That was a normal occurrence."

"At that point he decided to climb on top of me and he raped me."

'I've never raped anyone'

Mr Packer denied raping Ms Robertson and told the BBC: "I never touched her.

"I've never raped anyone in my life."

Ms Robertson made the allegations to police in 2006 and again in 2015, but has not had any further contact with the police.

Police Scotland Assistant Chief Constable Malcolm Graham said that in order to protect any potential legal case they were limited in what information could currently be released.

He explained: "An Advice and Guidance Report was submitted to the Crown Office and Procurator Fiscal Service (COPFS) in June last year, which presented the findings, so far, of the murder re-investigation.

"We have asked COPFS to consider this detailed report and await their direction on what further action should be taken.

"A number of alleged sexual offences were also uncovered as part of the ongoing murder investigation and these were reported to COPFS in June 2016."

"In relation to the previous investigation by Strathclyde Police in 2005, a preliminary assessment report has been sent to COPFS and we await further instruction."

The Crown Office declined to be interviewed for the programme. Given it was still a live investigation, they said "it would not be appropriate to comment further at this time".

Disclosure: Who Killed Emma? is available on demand on the BBC iPlayer.

Follow Samantha Poling and the rest of the investigations team on Twitter @BBCDislosure.