A former milkman branded 'pure evil' by police could spend the rest of his life in jail after being convicted of killing a schoolgirl in a 'frenzied and remorseless' murder more than 20 years ago.

Milkman Colin Ash-Smith, 46, stabbed 16-year-old Claire Tiltman to death in an alleyway in Greenhithe, Kent, in a 'motiveless attack'.

The Dartford Grammar School pupil was knifed at least nine times while on her way to a friend's house on 18 January 1993, just four days after her birthday.

Ash-Smith, who has been told he faces a life sentence, even attended the teenager's funeral wearing the jacket he had worn when he killed her.

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'Evil' Colin Ash-Smith is pictured above at Claire Tiltman's funeral - wearing the jacket he wore on the day he killed her

Colin Ash-Smith, 46, (left) has been found guilty of killing Claire Tiltman (right) in a 'frenzied attack' as she walked to a friend's house in Greenhithe, Kent in 1993

Ash-Smith had long been one of the prime suspects in Claire's murder, but it was not a 2003 change in the law allowing juries to consider past convictions that prosecutors had enough evidence to bring him to trial.

He was charged as a result of a cold-case review last year, when detectives searched his family home in Kent and interviewed his associates from prison - one of whom said Ash-Smith had described 'snapping' and stabbing a girl he had seen at a zebra-crossing.

As the jury of seven men and five women gave their verdict at Inner London Crown Court after around three hours of deliberation, blonde-haired Ash-Smith stared straight ahead stoney-faced.

Meanwhile Claire's friends, who had been in court throughout the five-week trial, broke down in tears.

The judge Mr Justice Sweeney warned Ash-Smith that 'the only sentence I can impose upon a conviction for murder is one of life imprisonment'. He will be sentenced tomorrow.

Claire's parents Linda (left) and Cliff Tiltman (right) never gave up hope her killer would be caught but both have tragically passed away before seeing Ash-Smith convicted of murdering their daughter

Ash-Smith was a serial attacker who had already carried out a horrific sexual assault on another local woman in 1988.

She was knifed five times in the back in a quarry and left for dead - an attack described by Ash-Smith as a 'masterpiece.'

Two years after killing Claire, Ash-Smith stabbed another woman in a street yards away.

He was jailed for life for those two attacks in 1996, which he is serving at HMP Belmarsh.

The stalker kept diaries of his deeds and jotted down details of attacks he intended to carry out.

Loner Ash-Smith was fascinated by Jack the Ripper and Superman, and took an obsessive interest in Star Trek. He even left a keyring bearing the show's logo at the scene of the 1995 incident.

Police closed off the road after 16-year-old Claire Tiltman was knifed in an alleyway in Greenhithe, Kent

Brian Altman QC, prosecuting, said Ash-Smith got a 'warped pleasure' out of killing Claire in a 'savage' and motiveless attack.

He told jurors: 'Her assailant had stabbed her no less than nine times in what can only be described as a frenzied and remorseless attack by someone having nothing less than the intention of killing her.

Brian Altman QC, prosecuting, said Ash-Smith (pictured) got a 'warped pleasure' out of killing Claire in a 'savage' and motiveless attack

'Make no mistake, this was a killing for the sake of killing, carried out by a ruthless and predatory armed killer, who attacked his chosen victim rapidly and stealthily, allowing her no time for defence or escape, and who fled the scene just as efficiently as he had arrived.'

His parents, Aubrey Ash-Smith and former Greenhithe mayor Diane Ash-Smith, stood by their son after his 1996 conviction.

They even persuaded his girlfriend at the time, Stella Murrell, to marry him in prison the following year, although she divorced him a few years later.

But neither of his parents was in court today.

The court heard Ash-Smith killed Claire just for the 'warped pleasure he derived from attacking a lone woman and the ultimate power and control it gave him.'

He called police the day after the stabbing and admitted being at the scene, but gave a fake alibi, claiming he had been driving his mother, the mayor, to see a constituent at the time Claire died.

Ash-Smith had a 'bizarre' reaction to Claire's death and even demonstrated how he murdered her on his girlfriend in the street a few weeks later. He even attended her funeral wearing the jacket he had worn when he murdered her.

Meridian TV footage of him at the funeral was shown to jurors during the trial.

Hundreds of detectives from Kent Police worked on the case - but Ash-Smith was only arrested after he confessed to a prison cellmate 18 years later.

Tragically neither of Claire's parents lived to see him brought to justice.

Mother Linda died of cancer in 2008 aged 56. Claire's father, plumber Cliff, died in 2012, also from cancer, aged 63. Claire's family said today's verdict meant the couple could finally 'rest in peace'.

Cliff Tiltman and his wife Linda (left) stand next to floral tributes to their daughter in 1993. Claire's killing sparked a major investigation by Kent Police (right)

Ash-Smith (pictured inside a police van in 1996) also stabbed a woman in 1995 in a street yards from where he had killed Claire

Ash-Smith described himself as a 'scumbag' and 'an animal' and admitted that he hates women because they make him feel 'worthless.'

He carried out his first attack on a 27-year-old married woman on December 21 1988.

He brandished a gun and a blade at his terrified victim as she was walking home alone from a night shift at 3am and dragged her to an abandoned quarry near Swanscombe, Kent.

He slashed off the woman's clothing with his knife and forced her to pose in obscene positions while he took photographs.

Throughout the attack he repeatedly plunged the blade into the ground just inches from her head and gagged her using toilet rolls.

Ash-Smith then bound the woman, repeatedly tried to rape her and attempted to strangle her with his school tie, before stabbing her five times in the back, intending to 'silence her forever'.

When his victim lapsed into unconsciousness he covered her body with dirt and leaves and fled the scene.

The woman spent the night naked on the freezing ground before regaining consciousness when she managed to crawl down an embankment to get help from some quarry workers.

She suffered life-threatening injuries and spent nine days in intensive care.

WHY IT TOOK 21 YEARS TO BRING 'LONER' COLIN ASH-SMITH TO JUSTICE Flowers were left at the spot where Claire was attacked. Her friends described how they coped with coming face to face with her killer in court Questions may be asked about why it took 21 years to convict Colin Ash-Smith of Claire Tiltman's murder. The former milkman was first questioned as a suspect in Claire's killing in 1995, when he admitted attempting to rape and murder a woman, and to stabbing another. But he always denied the murder, and police said they did not have enough evidence to charge him in 1995. At the heart of his trial lay the matter of Ash-Smith's 'bad character' - his past convictions for brutally stabbing two other women in 1988 and 1995 in attacks similar to the one on Claire. And his 'Assault Plans', detailed diaries in which he wrote about violent attacks he carried out on women, and many more he plotted. In an unusual step, the judge Mr Justice Sweeney allowed this to be admitted as evidence in the trial, and the evidence was the backbone of the prosecution case. Prosecutors have only been able to have this type of evidence heard following the 2003 Criminal Justice Act. But Nigel Pilkington, head of the Complex Casework Unit for the Crown Prosecution Service South East, said it took some years for the authorities to come to grips with how they could use this new provision. He said: 'Although bad character provisions came into force in 2003 we were all a bit unsure about how it could be used. 'What is very clear is we can't run a case on bad character alone. It wouldn't be fair to try somebody on just their record.' Officers said the trial of Levi Bellfield, who was found guilty in 2011 of murdering 13-year-old Milly Dowler, showed how bad character could be used to solve a cold-case murder. Milly vanished as she walked home from school in Surrey in March 2002 and her remains were found six months later. Jurors in his trial were told he had a string of convictions for attacks on young women. Mr Pilkington said bad character could only be admitted as evidence if it went to the 'propensity' or 'identity' of the defendant. In Ash-Smith's case, they said his bad character showed identity. He said: 'We say the similarities of this offending means that the person who attacked in 1995 had the identity of the attacker of Claire Tiltman. 'Bad character isn't just about previous convictions, it's about the other aspects of character - his sexual fantasies and his other assaults and attacks. The court heard Ash-Smith killed Claire just for the 'warped pleasure he derived from attacking a lone woman and the ultimate power and control it gave him' 'How likely is it that an attack of almost an exact, similar nature takes place in 1995, in which a person gets stabbed for no reason 14 times, and that is exactly what happened to Claire? 'This was an attack that was entirely motiveless, which is an extremely rare event. How likely is it that it would be repeated later? 'There are other similarities which are strikingly similar.' Ash-Smith was finally charged earlier this year after cold-case detectives reopened the investigation. There was one significant new piece of evidence. They interviewed Stefan Dubois, a former jail inmate who Ash-Smith confided details of Claire's killing to in what prosecutors said amounted to a 'prison confession'. But the case was mainly circumstantial as there was no direct or forensic evidence from the scene and no one witnessed the actual murder. The use of bad character was crucial to securing this conviction, and could encourage police and prosecutors to consider it in solving other cold-case crimes. Advertisement

Ash-Smith carried out his final attack on October 17, 1995 when he knifed 21-year-old Charlotte Barnard in a street just around the corner from where he killed Claire.

He drive around the town in his white Capri searching for a victim because he was in a 'bad mood' after driving in and out of London that day.

'I wanted to take my frustration out on someone, anyone, I didn't care,' the defendant told the jury.

'That's why I was driving around, looking for someone.'

Ms Barnard was walking along the pavement when he pounced on her with a blade and slit her throat.

He than dragged her across the road and stabbed her 16 times in the frenzied attack and only stopped when she fell to the ground and pretended to be dead.

Ash-Smith said he felt 'relieved' afterwards and added: 'I just wanted to hurt her and to take my frustration out on someone.'

Miraculously none of the victim's injuries were fatal.

A memorial (left) was set up for Claire Tiltman, who was brutally attacked by Ash-Smith in an alleyway (right)

Afterwards Ash-Smith went home to his girlfriend at the time Stella Murrell and spent a 'normal evening' with her at a local pub.

When he was arrested the next day, a search of his home unearthed blood-stained clothing, the knife used in both attacks and combat and war game magazines.

Police found the other half of the school tie from the 1988 quarry sex attack in his car.

They also found a stash of torture porn, and diaries describing the quarry attack in graphic detail.

CLAIRE'S LONG ROAD JUSTICE: HOW EVENTS UNFOLDED AFTER MURDER Claire Titlman (pictured) was stabbed in a dark alleyway as she walked to a friend's house January 18 1993 - Claire is stabbed to death in a dark alleyway as she walks to a friend's house in Greenhithe, Kent, four days after her 16th birthday. February 1994 - Milkman Colin Ash-Smith attends Claire's funeral with his father Aubrey and mother Diane, a local Labour councillor at the time. He wore the beige jacket he is said to have had on when he stabbed Claire. October 1995 - Ash-Smith stabs Charlotte Barnard, 22, at least 14 times in a frenzied attack ds from where he killed Claire. He is arrested by police, and admits the attack along with the attempted rape and attempted murder of a young mother at a quarry in 1988. He is also questioned as a suspect in Claire's murder, but not charged. December 1996 - Ash-Smith is handed three life sentences for the other two attacks. 2008 - Claire's mother Linda dies after fighting for 10 years to bring her daughter's killer to justice. September 14 2012 - Claire's father Cliff dies never having seen his daughter's killer come to court. Earlier in the year he issued a murder appeal from his nursing home bed. On his death Claire's school friends vow to take up the fight to find her attacker. September 2013 - Police search Ash-Smith's family home in Kent as part of a cold-case review into Claire's killing. February 12 2014 - The Crown Prosecution Service announce it is charging him with Claire's murder. November 6 - The trial begins and Ash-Smith is branded a 'predatory armed killer' by prosecutor Brian Altman. December 11 - Ash-Smith is found guilty of murdering Claire 21 years ago. Advertisement

They also found science fiction magazines and dozens of items of Star Trek paraphernalia.

The killer was obsessed with a number of other women and broke into two of their houses after stalking them for months.

He admitted wanting to rape one of his intended victims, the wife of a former colleague, and said: 'I was going to use the knife to threaten her to do anything I thought of at the time, probably sexually assault her..'

A list of fictional sordid sex fantasies with women he barely knew 20 years ago was found in Ash-Smith's prison cell last year.

Guilty verdict is a 'huge relief': The friends of Claire Tiltman who never gave up hope her murderer would be caught

It took 21 years for Claire Tiltman's killer to finally face justice, but throughout that time the schoolgirl's friends never gave up hope that her murderer would be caught.

Her school friends, now in their 30s and many with children of their own, sat through every day of the trial.

Claire's mother and father, Linda and Cliff, died never having seen her killer convicted.

But Claire's friends made sure her parents were not forgotten, propping a photo of the couple on the wooden bench where they sat at Inner London Crown Court. It was, they said, 'imperative' for them to attend the trial and see justice done.

Claire Tiltman (far left) with Lisa Gribbin (second from left) and her other friends at Dartmouth Grammar School for Girls

Friends of Claire Tiltman say they never gave up hope of seeing the murderer caught. Emma Edwards, Vicki Atkins, Joanne Roberts and Lisa Gribbin are pictured left to right

Friends of Claire Tiltman (pictured left as a child and right) sat through every day of the trial at Inner London Crown Court

They sat in the large courtroom next to detectives, some retired, who spent years trying to crack Kent's oldest unsolved murder.

Claire's friend, Emma Edwards, said: 'Her parents strived to get justice for her for so long, and although they are not here to see it in person they never gave up.

'To finally have seen justice through is a huge relief. We wanted to make sure her memory lived on, and she wasn't forgotten.'

Her best friend, Lisa Gribbin, travelled from her home in Scotland to attend the trial.

She said Claire should be remembered not just as a victim, but as a bubbly young woman from a close-knit family.

She said: 'We've spoken a lot about how much Linda and Cliff loved Claire. She was their world.

'But until now we've never talked about how much she loved them. They had one of the strongest bonds I have ever seen in a family.

'EVIL' ASH-SMITH 'NEEDS TO BE BEHIND BARS', SAY DETECTIVES Detectives branded Claire Tiltman's killer Colin Ash-Smith 'pure evil' and said he should never be free to walk the streets again. Officers warned the former milkman was 'always looking, stalking - always looking to attack women' and would have pounced on hundreds more if he had the chance. Detective Superintendent Rob Vinson, from the Kent and Essex Serious Crime Directorate Cold Case Team, said the murder was one of the most 'horrific' and 'emotive' cases he had worked on. He said: 'Ash-Smith is a very dangerous individual. He is a predator. He would be stalking women with evil intent (to carry out attacks) - some of which he carried out and some of which he didn't. 'On the night in question Claire was in the wrong place at the wrong time Blonde-haired Ash-Smith stared straight ahead stoney-faced as the jury of seven men and five women gave their verdict at Inner London Crown Court, pictured 'When you look at the writings and some of the things he has done, this is a very, very dangerous individual, and justice has been served at last for the brutal murder of Claire." Asked if Ash-Smith should ever be freed, he said: 'This is an evil man and he needs to be in prison.' He revealed that Ash-Smith had long been one of the prime suspects in Claire's murder which took place in an alleyway near her home in Greenhithe, Kent. But it was not until changes in the law were made allowing a defendant's past convictions to be put before a jury that prosecutors had enough evidence to bring him to trial. Nigel Pilkington, head of the Complex Casework Unit for the Crown Prosecution Service South East, said Ash-Smith would have attacked many more women if he had the chance. The final moments of murder victim Claire Tiltman were reconstructed by BBC One's Crimewatch UK programme He said: 'He is a man who is always looking, stalking - always looking to attack women. The fact he only attacks some of the time is because he is not going to attack if he is going to be seen. 'He is thinking about it (attacking) all the time. How many times has he thought about doing it and then abandoned it? Probably hundreds of times. 'I don't think he can help himself because he is in a "psycho state of mind". If you ask him if he wanted to kill Claire Tiltman, I think he couldn't stop himself.' Claire's parents, Cliff and Linda, have died in the two decades since her killing and Mr Vinson said their deaths made officers more determined to catch Claire's killer. Advertisement

'Her parents were her idols, and she was never embarrassed to say that or to show it.'

Known affectionately to her friends as Tilt, Claire was no pushover.

Feisty, fiercely loyal and with a wicked sense of humour is how her friends fondly remember her.

A music-mad teenager, she shunned the usual boy bands, preferring to dance around her living room to Australian rock band INXS and Queen.

Ms Gribbin said: 'She was a really loyal friend. She had a cheeky, almost wicked sense of humour.

'Very dry and very quick-witted.'

Always neatly turned out with perfectly manicured nails and hair, Claire aspired to be a firefighter.

But her dream was cut tragically short when she was killed in an alleyway near her home in Greenhithe, Kent, just four days after her 16th birthday.

Her friends said coming face to face with her killer in court was tough, but in some ways therapeutic.

Claire's parents went to their graves convinced Ash-Smith was Claire's killer and with today's verdict may they finally rest in peace

They had prepared themselves for a knife-wielding monster, and were presented with a baby-faced killer.

Joanne Roberts said: 'It may have laid a lot of demons aside, seeing him. We have all been scared of this murdering monster. It took a long time to get used to this reserved man with his squeaky voice.'

She said the trial answered many questions that had hung over them for more than two decades.

'The only question that has not been answered is why,' she said.

'We know how, where and when, but we'll never know why.'

Claire's family said the guilty verdict means her late parents can finally 'rest in peace'.

David Withers, the deputy senior investigating officer, read a statement outside court as Claire's friends stood either side of him holding up photographs of the murdered schoolgirl.

In it, the family said: 'A big thank you to the Kent Police who never gave up trying to find Claire's killer. We would also like to thank Claire's friends.

'Claire's parents went to their graves convinced that Ash-Smith was Claire's killer and with today's verdict may they finally rest in peace.'

Speaking in an interview from his death bed before he died, in 2012 Cliff Tiltman said: 'We know he did it, the police know he did it.

'I just wish he would've confessed to it all those years ago and saved us all this agony.