Murder victim had skull smashed by hammer and body buried in concrete - and killers nearly got away

When a caller with a heavy French accent confessed to murdering his flight attendant flatmate four years earlier and entombing his body in concrete in his garden, police inspector Anton Sullivan listened in horror.

It sounded like the plot of a Mafia movie but, as his three year investigation proved, every word of the bizarre late night phone call made by Sebastian Bendou in 2013 - four years after his victim was reported missing by Ryanair colleagues - was true.

The murder victim - buried at the bottom of the garden in Ellesmere Port, Merseyside - was fellow Frenchman Christophe Borgye, 36. Meanwhile, a man has been crushed to death by his wife after she 'stumbled and fell on top of him'.

Now the gruesome story is being told in a new Prime Video documentary, Murder in Concrete, screening from August 31.

“The ripple effects from this crime are still going on a decade later,” Anton, who retired in January after a career spanning more than 30 years and appears in the documentary, tells The Mirror.

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Christophe’s love of travelling brought him to the UK, where he landed his airline job, but fell in with three men who went on to kill him.

Unemployed Dominik Kocher, a German national who was married with a family, had welcomed Christophe when he moved into the rented home opposite him, where his cousin Manuel Wagner lived with Frenchman Bendou, a paranoid schizophrenic.

Anton says Kocher left “a trail of fraud behind him,” in Europe, before settling in Merseyside.

Somehow, the experienced conman - who also lied about having cancer - persuaded all three men to let him run their finances.

“Kocher controlled everything to do with Bendou and Wagner,” explains Anton. “He took their money and in exchange he did their cleaning and cooking. It was like they were his children.”

Christophe soon accepted the same deal - handing over his wages.

“Kocher is a very convincing, very manipulative individual,” says Anton. “The deal he presented was, ‘I know you want to travel, I know that you work long hours and irregular shifts. I will look after everything for you, you pay the rent, and because I have cancer and don’t work, I look after everybody in the house.’”

Kocher was known in the area for ripping people off, according to Anton, who describes Christophe as “a very caring person.”

Anton adds: “He took people on face value, and if they were nice, kind, and sympathetic, he just presumed that's how they were.”

For a few years, the four men lived comfortably with the arrangement.

But in the spring of 2009, Christophe said he was moving to Belgium to advance his career.

“Kocher realises this means the tens of thousands of pounds he’d been taking off Christophe for the last two years was disappearing,” says Anton. “He has to persuade Wagner and Bendou, who is particularly vulnerable, to get involved in getting rid of Christophe.

“Kocher starts feeding them a narrative that Christophe is a clear and present danger to the family; that he’s a spy who wants to get them out of the way so he would have access to Kocher’s eldest daughter.”

In April that year, Kocher bought three supermarket paring knives, together with bricks, cement and limestone chipping from a nearby builders’ merchants.

On the morning of Christophe’s death, the three conspirators lured him downstairs to their specially prepared ‘kill room’ in the kitchen, which had tarpaulin laid down for the job. Wearing plastic overshoes to minimise blood spatter, they stabbed him as he desperately tried to fight them off.

Anton explains: “The knives were cheap and not up to the job, so Wagner produced a claw hammer he’d brought along. Those blows to Christophe’s head were what killed him, there was catastrophic damage to the skull. The victim never stood a chance.”

The killers then wrapped Christophe’s broken body in the tarpaulin, carrying him to an outhouse, where they built a shallow wall around his body, then filled it with concrete.

“The three of them, having cleared up the blood and mess, then decide they’re a bit peckish and go to Chiquitos for lunch,” marvels Anton. “We later find the credit card receipt from Kocher’s bank. Then they continue to live their lives in that house, with what they’ve done, for some time after the murder.”

Kocher even sold Christophe’s possessions and pocketed the money.

After Christophe’s concerned colleagues reported him missing, someone - believed to be Kocher, who has always maintained his innocence - emailed the Borgye family, masquerading as Christophe, saying he’d met a Chinese girl and was moving.

Anton says: “It’s made to look as though Christophe has written it, with little elements of things he liked, like a new Wolverine film and so on.

“But then it talked about him having a midlife crisis, his phone’s about to die, he’s gone off-grid and when he’s settled in China he’ll contact them. That was out of character.”

Christophe’s worried brother and sister, Noel and Aurélie, contacted Cheshire Police, but his killers again covered up his disappearance.

For four years, Christophe’s body lay undiscovered in its concrete tomb.

Kocher and the other men eventually moved to Warrington, then to Dumfries in Scotland, telling the new Merseyside tenants not to use the outhouse as it was the landlord’s store.

But Bendou’s 2013 call to police triggered the investigation that exposed the truth.

Bendou had become increasingly paranoid, thinking Kocher and Wagner were planning to kill him and dispose of his body in a similar way.

Arriving at the police station “dishevelled,” Anton says: “He hadn’t washed in a couple of days and it was difficult to understand him.”

He claimed he had killed Christophe alone during a fight, in self defence.

Bendou led cops to the outhouse where he was entombed.

Retired Detective Sergeant Steve Currie, who was there, says: “There was a brick-built structure at the back of it at the bottom which just didn't feel right.

“That's the moment for me when I thought, ‘This thing's got legs’.

“It took four days to get the body out. We found Christophe wrapped in a coat, other bindings, butcher's coats and the tarpaulin sheet.”

Three knives and three pairs of shoes were found with the preserved body, indicating Bendou hadn’t acted alone.

Soon after Kocher and Wagner were fingered. Both stood trial in 2014, and Kocher was convicted of Christophe’s murder. Wagner was cleared of assisting an offender and preventing a lawful burial, but later convicted of murder in a separate trial, after Bendou told how he had made the first hammer blow that killed Christophe.

Bendou admitted to killing Christophe, claiming diminished responsibility, but was handed a life sentence with a minimum of 14 years.

Wagner and Kocher have never admitted guilt.

Meanwhile, Christophe’s family - who have been involved with the documentary - say every life event he misses triggers their grief.

“Christophe never got to meet his nephews. He missed Aurélie’s wedding,” says Anton.

“These are all important milestones for the family that Christophe has not been there to share.”

Timeline

April 2009: Christophe is killed by three ‘friends’ and entombed in concrete in the garden

May 2009: Ryanair colleague reports Christophe missing. Someone impersonates him in an email to his family, saying he’s safe.

November 2012: Kocher and his family, Bendou and Wagner move to Warrington and afterwards to Dumfries, Scotland.

April 13, 2013: Bendou travels to Ellesmere Port and confesses to the crime, at first saying it was just him.

April 17, 2013: Wagner and Kocher questioned as witnesses. Wagner alleges Christophe is living in China.

May 2013: Bendou tells police about Wagner and Kocher’s involvement. They are arrested on suspicion of murder, which they deny.

July 2013: Kocher and Bendou charged with murder.

March 2014: Kocher convicted of murder, Wagner cleared of assisting an offender and preventing a lawful burial.

May 2014: Bendou convicted of murder. Later sentenced later to life with a minimum of 14 years.

June 2014: Appeal to increase Kocher’s sentence rejected. His sentence is life with a minimum of 23 years.

September 2016: Wagner, now living in Liverpool, charged with murder.

June 12, 2017: Bendou testifies against Wagner.

June 28, 2017: Wagner convicted of murder and sentenced to life with a minimum of 16 years.

*Murder in Concrete launches on Prime Video on August 31

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