Detectives are to revisit a lay-by near Wolverhampton where the body of murdered prostitute Janine Downes was dumped 20 years ago.

The mother-of-three’s half-naked body was discovered hidden in the lay-by two miles outside Shifnal on February 2, 1991.

Detectives from the West Mercia Police major incident unit will visit the spot on Wednesday  the 20th anniversary of her death.

They believe that someone knows the killer, and today they urged them to break their silence.

It is one of the force’s oldest unsolved murders. Miss Downes’s body was found just before 9.30am on the A464 Wolverhampton to Shifnal road. Several arrests have been made over the years but no-one has ever been charged.

Det Chief Inspector Neil Jamieson, who is leading a cold-case review into the murder, hopes that officers visiting the spot where she was found will trigger someone’s memory and remind them that her killer is still at large.

Mr Jamieson said the case sparked “huge interest” at the time, with many people coming forward with information and several arrests being made.

He said the post mortem revealed that Miss Downes had been strangled, suffered extensive head wounds and had been sexually assaulted.

Mr Jamieson said: “Marks on the frosty ground indicated that Janine had been dragged to the spot where she was found, and a pathologist estimated that her body had been dumped there between midnight and 4am.

“We continue to seek that vital piece of evidence that will point us in the direction of an individual, whether that is someone we already know about from the original inquiry, someone who has come to our attention since, or a person we do not yet know anything about.”

He added: “We are convinced that there are people who know who killed Janine, and, 20 years on, we are hoping someone will decide it’s time to come forward so that we can finally bring Janine’s killer to justice.”

Miss Downes, who had given birth to her third child months before her murder, was wearing only a paisley patterned blouse, a bra and blue ankle socks when her body was found.

Her other clothes  white trainers, blue jeans and a black shell-suit top with a yellow stripe bearing the words Nike International  have never been found.