In the space of 15 months at least 11 women in Liverpool became victims of a calculating predator patrolling the streets in a black cab.
By 1990, the horrendous crimes of the moustached sex offender had brought enormous pressure on Merseyside Police detectives to get him off the streets. The pervert had attacked at least 10 victims who flagged down his cab, while an 11th woman, believed to have been a sex worker, was abducted and raped in the Sefton Park area while he was off-duty.
With DNA analysis a relatively new phenomenon, senior officers commissioned the remarkable Operation Hackney, one of the biggest investigations of its type in the force's history - eventually identifying 29-year-old Frederick Manssuer of Croxteth Lane, Prescot, as the incredibly dangerous sex criminal.
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Police used a designated area of the Kings Dock in the city centre to encourage all 6,000 registered cabbies in the region to come in to be interviewed and have their photos taken for "elimination purposes".
This is the story of how that operation took down one of the most dangerous sex offender's the city has seen.
The attacks were broadly similar, on lone passengers usually in the early hours of the morning. The suspect, described as of muscular build and with a moustache, would suddenly veer away from the passenger's intended destination before stopping in a secluded area and forcing himself on the terrified women.
In one particularly harrowing 1989 case, a 38-year-old mum of two was dragged from the cab by her hair in the car park of a sports centre in Stanley Park, Anfield, and raped.
Several of the victims managed to fight him off. As the attacks continued and the evidence pointed to the same offender, trapping the serial rapist become the top priority for Merseyside Police's Serious Crime Squad.
The ECHO previously spoke to retired Detective Superintendent Albert Kirby, then the head of the Serious Crime Squad which handled the investigation, about what happened.
He said: "Manssuer was a horrible, objectionable man who lived up to the type of conduct and behaviour that he had inflicted on those women. He really was an absolute slimeball.
"We were never able to say for sure, but I remember one witness had described seeing him clean out his cab in the early hours of the morning. The gentleman saw he had a pair of women's underwear in the back of his cab, and Manssuer made some excuse that he had picked up a woman who could not afford the fare so he had his evil way with her instead.
"It is not unusual in these kind of cases that he could have been keeping trophies from his victims."
Taxi drivers in the city were also keen to help root out the predator in their ranks, making women feel unsafe to use their services.
Mr Kirby, who also headed the investigation into the murder of James Bulger, told the ECHO: "Frederick Manssuer was subjecting all sorts of women to really obscene behaviour, and to the best of my recollection it was not an easy investigation.
"We had to launch Operation Hackney, and it really was a big operation.
"I distinctly remember, and because my brother-in-law was a taxi driver, I used to hear from him how the taxi drivers were only too happy to come in and help clear it up. They were being tarnished with the same brush, and it was difficult for the 99.9% of them who were hard-working, law abiding and generous people. They had this stigma."
The massive task of speaking to every cabbie in the region began on July 17, 1990. Hundreds of drivers turned up each day to help in the investigation.
'A very strange bloke'
What police did not know in July 1990 was that Manssuer already feared that they were closing in on him. His business associate and friend Alan Gore, then 43, had a half-share in a black cab with Manssuer, and told the ECHO at the time about a strange conversation the pair had before Operation Hackney began.
The rapes had already begun to generate publicity, with detectives telling reporters on the crime beat that they suspected one or two taxi drivers were responsible for the vicious attacks. In September 1989, the ECHO front-page carried a photo-fit image of a suspect who had tried to rape a young woman in his cab, one which turned out to be reasonably accurate.
Mr Gore, from Huyton, told reporters how one day Manssuer strode up to their cab grasping a copy of the paper. He said: "He suddenly came up to me one day and said 'look they've got a photograph of the rapist in the paper'.
"It was a very strange incident; you could see he was in a panic. "He added: "Fred was a very strange bloke indeed."
It was, in fact, a conversation with Mr Gore that eventually led to Manssuer's downfall. Despite Manssuer's reluctance, Mr Gore was able to persuade him to head down to King's Dock to be interviewed by police as part of the dragnet operation.
Manssuer told detectives he had a licence to drive cabs in Knowsley, but did not mention he had also held a licence with Liverpool City Council for years. The pair were among around 2,500 drivers who turned up to be interviewed, and their attendance meant the painstaking police operation paid off.
In September 1990, as part of their enquiries, detectives asked a sister of one of the victims, who had also caught a glimpse of the attacker, to look through some photos they had gathered during those interviews.
She had no hesitation in picking out Manssuer.
Confident they had their man, detectives began to look into Manssuer's past and made a worrying discovery. It emerged that two years earlier, Manssuer had tried to kill himself and officers had been called to a house in Knowsley where they found him bleeding from self-inflicted wounds to his neck and wrists.
When police approached him he was reported as muttering that he should be "left to die" before suddenly lunging for the officers, claiming he had Aids. Manssuer reportedly tried to bite the arresting officers and smear them with blood before he was restrained, leaving them facing an anxious weeks-long wait for test results, which thankfully returned negative.
Alarmed by the facts of that previous case, the police planned the arrest of Manssuer on rape charges carefully, with officers donning protective clothing. In the end Manssuer, who lived with his wife and young son, came quietly.
The case moved rapidly from there, and the relatively new technology of DNA testing quickly linked Manssuer to three rapes - with detectives planning to grill him about many more offences. Mr Kirby and his team were also able to confirm that Manssuer was indeed HIV positive, meaning more trauma for his victims who required tests.
The results of those tests remained private, although officers at the time told the ECHO it was not believed he had transmitted the virus to his victims. Satisfied to have got the right man, the officers involved did not know the investigation was about to hit a tragic wall.
Justice denied
On September 28, 1990, Manssuer made his first appearance in court charged with the rapes of three women. Ahead of what was expected to be a major trial, the suspect was remanded in custody and carted off to Walton prison to await the next hearing.
But a serious mistake was made in processing the prisoner. An important piece of paperwork, highlighting that Manssuer was a suicide and HIV risk, was not passed to prison officers transporting him to Walton. The mistake meant he was locked up in solitary confinement rather than the prison's hospital wing, where he would have been under supervision.
Just before midnight that same day, Manssuer was found hanging in his cell and was later pronounced dead. An inquest jury returned a verdict of suicide.
Mr Kirby told the ECHO: "I felt very, very sorry for the women involved, they were denied the chance to see justice done because he took his own life. And my staff worked very hard on the operation. I feel like we only scratched the surface in relation to his perverted sexual activities.
"There would no doubt be further offences that he committed that were not identified."
Another senior officer who worked in Mr Kirby's team, Detective Inspector David Byrom, told the ECHO at the time: "This was a huge inquiry which none of us involved with it will ever forget. Obviously it is unsatisfactory that justice was not allowed to run its course.
"Manssuer's death at Walton Jail came as a great shock - it was not the way we wanted things to turn out."
While Manssuer was hauled off the streets before he could hurt anyone else, detectives feared he may have been responsible for attacks going back to 1987. The full extent of his crimes will likely never be known.
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