COLD case detectives are reviewing the unsolved killing of a young woman whose body was found at a remote woodland spot 10 years ago.

Despite four arrests, an exhaustive investigation, and a Scotland-wide manhunt, the murder of Emma Caldwell in April 2015 has remained unsolved.

She was last seen near a women's hostel in Govanhill, Glasgow, and her remains were discovered near Roberton, Lanarkshire around a month later.

In 2007, four Turkish men were arrested in connection with the death of the 27-year-old but the case against them later collapsed.

Detective Superintendent Bobby Hendren, Homicide Governance and Review, said: "April 2015 will be the 10th anniversary of Emma's death.

"Her murder is still very much an open investigation which, as with other unsolved cases, is under constant review.

"We are committed to keep working on her case until we bring her killer or killers to justice."

Miss Caldwell was a former stable girl, and happy teenager, who had grown up in Erskine, Renfrewshire. But in 1998, her elder sister Karen died of cancer and within a year, Miss Caldwell had become hooked on heroin and worked as a prostitute in Glasgow to feed her habit.

She was last seen on April 4, 2005 near a women's hostel in the Govanhill area, at around 11pm.

Her body was discovered in woods near Roberton, Lanarkshire around a month later by a dog walker.

One police insider said: "Whoever committed this horrendous killing - and kept it a secret for 10 years - must remember there is no expiry date on justice."

It is believed Miss Caldwell, who was strangled, may have spent her final night with the driver of a Skoda Felicia.

Detectives tracked down the owners of every Skoda Felicia in Britain after CCTV footage showed a woman entering one on the night Emma went missing.

However, none admitted to being in the Broomielaw area of Glasgow.

More than 2,700 statements were taken as part of then Strathclyde Police's biggest murder investigations and finally four men were arrested.

Huseyin Cobanoglu, now 63, from Irvine, Halil Kandil, 42, from Cadder, Abubekir Oncu, 39, from Springboig and Mustafa Soylemez, 44, were charged with strangling Miss Caldwell at the Turkish Community Cafe in Glasgow's Bridge Street in 2005.

They were also accused of attempting to pervert the course of justice by dumping her body in woods.

However, within a year, the case had collapsed.

The Crown Office had 12 months from the date of the arrests, to set a trial date, but in July 2008, it emerged that prosecutors had been unable to do so within the deadline.

Despite a massive investigation, hundreds of interviews and thousands of man hours, her parents William and Margaret are still waiting for answers.

A Crown Office spokesman said: "COPFS maintains a database of cold case homicides.

"The Cold Case Unit works closely with Police Scotland to review these cases to ascertain if there are any new evidential developments, including advances in forensic techniques, which would assist in providing a basis for criminal proceedings.

"There is a risk of prejudicing fresh prosecutions by commenting further on individual cases or providing details on how a particular case is being dealt with.

"It would therefore be inappropriate to comment further at this time."

It is understood around 8,000 names remain on file and the case is being reviewed every 18 months by the specialist homicide governance review unit.