Pamela Jackson: The Full Story - How police cracked the complex case

The investigation into the disappearance of Pamela Jackson in March this year became one of the biggest in the history in the Durham Police Force.

It began as a missing person's inquiry after the 55-year-old grandmother vanished from her Chester-le-Street home.

But very soon police began to suspect her partner Adrian Muir may have killed her after Pamela's family told them he was behaving nervously and had already changed his story about the last time he saw her.

In the weeks and months that followed 165 officers and specialist police staff would be involved in Operation Sorrento - using a wide variety of investigative techniques to eventually prove Muir had killed Pamela or "Chrissie" as she was known.

Soon after he was first arrested, police used vehicle tracking technologies and established that on the last day Pamela had been seen alive, Muir had driven late at night from her home town in County Durham, heading south down the A1 and on into West Yorkshire. Could this have been where he buried Pamela's body, police wondered?

Next, officers analysed Muir's mobile phone records and established that later on that same night he had parked up on a remote road on Cragg Vale moors near Halifax. The stonemason was making internet searches and sending Facebook messages from somewhere along the B6138.

The problem was that the road and the moors still left detectives with an enormous search area. With no body and without further concrete evidence, Muir's guilt would be much harder to prove to a jury.

Officers also realised Muir could have buried Pamela anywhere along the 120-mile journey from her home to the moors road and so had to make a number of other searches.

There was also still a possibility at that point she might turn up alive so "missing" posters continued to be posted at a wide variety of locations.

In late March the investigation hit a set back. The search for Pamela was still mainly focussed on the moors but the snows that caused so many problems for farmers in the lambing season were also proving a nightmare for the investigation team. The B6138 was blocked and it was around five weeks before trained officers could begin looking for a body there again.

In early May though the investigation had a lucky break. Moorland fires broke out in the search area near Halifax, stripping back vegetation and making the landscape much easier to scour for clues.

A dog handling team noticed cracks in the soil that looked as if there might be a shallow grave - they were right - Pamela's body was found inside.

The news in some ways was an enormous relief for Pamela's large and loving family. By now they had come to accept the police's conclusions that she had been killed but they desperately wanted to bring her home for a proper burial.

But the discovery also yielded a whole host of evidence that would help pin Pamela's killing firmly on Muir, a man she had met on an internet dating site.

Soil samples from the burial ground were analysed and found to closely resemble soil found in the footwell of Muir's car and also on his gloves.

Fibres inside the silver Kia were also matched with fibres found in the grave.

Muir had also buried Pamela with a bunch of flowers wrapped in a carrier bag. Was this at least some sign he had felt sorry for his crime?

Either way the flowers gave detectives a major new piece of evidence as a lone print was found on the shopping bag the flowers were wrapped in and it was the thumbprint of Adrian Muir.

After studying hours of CCTV footage Durham Police also found pictures of Muir in a supermarket car park in Chester-le-Street, two days after the killing, scrubbing the back of his car clean with products he had just bought from Morrisons.

Further investigations of his mobile phone also brought to light a number of recordings Muir made on the night of the killing seemingly confessing to the crime and suggesting he was contemplating suicide.

Despite all this weight of evidence, though, Muir insisted he knew nothing about what happened to Pamela, telling a jury at his trial at Newcastle Crown Court that he thought he was being framed and explaining other elements of the crown's case as simply co-incidence.

Today though the lies he told and the secret he tried to bury up on the moors finally caught up with him after a jury found him guilty.