MYSTERY still surrounds a 'kidnap' in Herefordshire, ten years after it sparked a major police operation.

This week marks a decade since a Europe-wide police alert went out in 2011, as detectives on Operation Vaporise worked to pluck a woman out of thin air.

That woman was last seen being bundled, unconscious, into the back of a van by a group of men on a darkened rural road near Hereford, according to a "very reliable" witness.

But thin air is as substantive as it gets over the identity of the victim and her whereabouts, with no woman matching the description reported as missing.

Given what there was to work with, Vaporise is one of the most unusual police inquiries undertaken in the county over recent years.

But Detective Inspector Martyn Barnes said at the time that his team had to start thinking the worst of what started as a “suspicious incident."

“The more time goes on, the harder it is to see an explanation for what went on as anything other than sinister,” said DI Barnes.

Vaporise – which went to full operational strength in April 2011 – relied on the word of a single eyewitness whose story had been tested several times by specialist interviewers.

Her account of what she came across on the Ridgeway Road between Sutton St Nicholas and Withington at around 9pm on Friday, March 25 2011 was re-constructed on the same stretch of road.

She told detectives she saw a woman who appeared unconscious being carried by four men from a black BMW X5, facing one way, into a dark coloured panel van facing the other. The eyewitness’ offer of help was robustly refused by the men.

In days, Vaporise had put the incident and related descriptions out to police across the UK, swiftly going Europewide through Interpol.

With any possibility of the “kidnap” being staged as an exercise by special forces or private security ruled out, Vaporise got on with tracing the owners of all 88,053 black BMW X5s in the UK, starting with the 277 within HR postcodes alone. This element of the investigation was also extended to company cars and those out on hire.

Several leads generated by the reconstruction, related publicity and intelligence sources also emerged and needed to be investigated, offering various scenarios as to what could have gone on.

“If there is an innocent explanation for all this, it is not too late to come out and say so, but, everything we are working with so far suggests there should be real cause for concern about what went on and what has happened to this woman,” said DI Barnes in April 2011.