POLICE officers who took part in the investigation into the murder of six-year-old Alesha MacPhail have told of the “huge impact” of the case on themselves and colleagues.

Alesha was visiting family in Rothesay, on the Isle of Bute, when she was abducted from her bed, raped and murdered by 16-year-old Aaron Campbell, on July 2, 2018.

Her body was later found in woodland nearby. She had suffered117 separate injuries.

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Alesha’s killer was caught after he was captured on his mother’s CCTV coming and going from their home in the middle of the night.

Speaking in BBC documentary Murder Case – Inside The Inquiry tonight, officers from Police Scotland’s Major Investigations Team reveal the toll the case took on staff.

Detective sergeant Julie Nedley said: “It was my team that investigated the Alesha MacPhail murder and for the officers that were working on that, they were exposed to some horrendous things.

“Obviously that’s not a patch on the suffering that her family have endured. However, I remember being in the office the first Friday that all of my colleagues came back from the island. Some of them just looked ill -- they looked physically traumatised.”

She added: “I remember the day of the verdict, being in the office. It was very emotive, there were people upset. A case like that can have a huge impact on you as a police officer and on the department.”

DS Michael McCarron, Police Scotland’s family liaison officer during the investigation, told how it was his job to keep Alesha’s mother, Georgina Lochrane, informed of progress in searching for her daughter and, later, her killer.

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He said: “Quite often we deal with murder of the completely innocent and they just happen to be at the wrong place at the wrong time, and they contributed nothing to what happened to them.

“The saddest ones you’ll ever get are children. She was only six years old that wee girl, and she was abducted, raped and murdered by a 16-yearold boy on the Isle of Bute.

“It was just about the most tragic set of circumstances. Out of all the jobs I’ve ever dealt with I would say that was the toughest job I’ve had in the police.”

DC Graeme Bettley added: “It was the first time in an inquiry I’ve become aware of people becoming emotional in work, because as the inquiry progressed and more and more information became available we became aware of how much of an horrific murder it was.”

The hour-long documentary gives a unique insight into the work of the police team, who deal with around 60 murders per year in Scotland. Following senior and rookie detectives, it reveals what it is like to work on harrowing cases, in the worst crime scenes and deal with most disturbing offenders in the pursuit of justice.

Detective Constable Gemma Lawrie, who has been on the force for 11 years, discusses her part in the investigation into the murder of Irish student Karen Buckley on April 11, 2015.

The 24-year-old had gone out with friends to The Sanctuary nightclub in Glasgow. Also there that night was 21-year-old Alexander Pacteau, who would later be jailed for life for her murder.

Pacteau repeatedly struck her with a spanner and strangled her in his car before hiding her body in a barrel.

DC Lawrie said: “The first high-profile murder that I worked on was the Karen Buckley murder.

“On that inquiry I did CCTV for the nightclub that Karen was in.

“I’ll never forget it. It’s horrible, to watch an innocent girl in a nightclub having a good time with her friends -- it’s like that sliding door moment. She leaves and walks into her death.”

The programme also sees Detective Inspector Peter Crombie overseeing the search for a knife, thought to have been disposed of in the River Clyde.

Instead the underwater unit recovers a host of other weapons from guns to machetes.

He said: “I’m sure there’s been loads of items that have been discarded in there over the years.

“I think they pulled everything but the kitchen sink from the dock that day.

“They did recover a machete and several knives and guns but unfortunately there was nothing linked to our investigation.

“Unfortunately the reality is that we can work away for weeks and months on an inquiry before we get the answers we are looking for.

“But it’s that determination to get the answers for the victims because they don’t have a voice, and it’s up to us to try and get the answers for them.”

Murder Case - Inside The Inquiry is on BBC Scotland tonight at 10pm-11pm, repeated on BBC Two tomorrow at 9pm-10pm