Viktoria Chagaeva, 46, who owns a beauty salon in Angarsk, with a picture of her beloved younger sister Tatiana, killed by the 'Wednesday murderer'. Picture: The Siberian Times

The married serial killing former cop, Mikhail Popkov, 49, forced victims to strip naked before killing them and having sex with their blood-soaked bodies. He has been charged with, and confessed to, the murder of 24 victims, but police had suspected him of a total of at least 29 killings and one attempted murder.

Of these, 25 were aged 19 to 28, and four were from 35 to 40. He selected victims who were full-figured, and not tall, say police sources.

He beheaded at least one woman and gouged the heart out of a victim.

Popkov claimed he suddenly stopped killing after he 'became impotent', suggesting a sexual motive to his murder spree. Typically, his victims were slightly intoxicated when he lured them to their deaths. He snared them after they had been to bars or parties. He is suspected of seeking revenge on his mother who was an alcoholic and allegedly abused him in his childhood.

'I used to work closely with him for 5 years. He knew lots of jokes and stories, and could be soul of the party', a colleague said of the 'Wednesday murderer'. Picture: The Siberian Times

At least one crime expert believe he committed more than the 24 murders he admits, and may have been behind unexplained killings as far away as Vladivostok where he travelled frequently after leaving the police, say reports. Originally labelled the 'Wednesday Murderer' because many of his victims were found early on this day of the week, his reign of terror continued from 1992 to at least 2000. Police have been unable to prove any killings since then, even though he was only finally arrested on 24 June 2012.

One detective hunting him labelled him a 'werewolf'. His first murder happened 'spontaneously', Popkov told investigators.

'I just felt I wanted to kill a woman I was giving a lift to in my car', he said. Popkov, married with one daughter was finally caught after analysis of the DNA of 3,500 policemen and former policemen in Irkutsk region, where the murders took place. As a result, they obtained a 100% match with his sperm that was found on some of his victims.

Earlier, police were severely criticised for failing to catch a sexually-motivated killer, and ignoring vital evidence. He murdered the women with a slipknot, knife, awl, screwdriver or an axe which he used up to 17 times on some victims. He used his police uniform and car to gain the trust of at least some of his victims. Key clues came from a failed attack on a teenager called Svetlana M, 15 years ago. She was 15 at the time but looked older, said police.

On 26 January 1998, she told how a police car stopped near her and offered to give her a lift. He took her into woodland where he forced her to take off all her clothes. He then smashed her head against a tree. She lost consciousness and next day was found alive near the village of Baikalsk, somehow surviving despite being naked in sub-zero temperatures. She awoke in hospital.

The maniac's victims, top to bottom - Yulia Shapovalova and Maria Molotkova; Maria Molotkova funerals, and pictures of two other victims, Marina Lyzhina, 35 (l) and Liliya Pashkovskaya, 37 (r) at their funerals. Pictures: The Siberian Times

For years police suspected the killer's job was a metalworker, driver, railway employee or heating station engineer. Or even a cemetery worker. Even Svetlana's evidence was not properly acted upon and only much later did the police understand that the killer was one of their own. Born in 1964, he worked as a policeman before becoming a security guard for Angarsk Oil and Chemical Company - big city industrial complex, and later for a private security agency.

His wife Elena, 47, was also in the police, and his 26 year old daughter Ekaterina is a schoolteacher. It is not believed his family - who thought of him as a 'perfect husband and father' - were accomplices, even though on two occasions his wife gave him alibis when suspicion focused on him.

One victim gave Popkov syphilis. The police knew the dead victim had the disease, and also discovered that Popkov had contracted it.

'It was enough just to perform a DNA test of this man but the police interrogated Popkov's wife who composed an alibi for her husband,' said Nikolai Kitaev, an ex-police investigator who is critical of the handling of the probe. 'Later he became more careful and carried on with his horrific crimes.'

The next occasion was the case of Svetlana M, the survivor. 'She was unconscious because of severe head injuries. Police did not start a criminal investigation for a long time despite numerous complaints from the girl's mother'. Svetlana was questioned 'and told in detail about her rapist-policeman and his car'.

She was shown a picture of him and his police car. 'She clearly confirmed it was him. But again, the police trusted Mikhail's wife - once more she composed an alibi for him and the criminal investigation was stopped and sent to the archives', Kitaev said.

Kitaev is convinced there are at least a dozen more cases in police files that are likely to be Popkov's victims. Many of the details from the crime scenes match his modus operandi, he said. One of the investigators who probed the Popkov case, Mikhail Zavorin, described in 2003 the traits of the killer they were still hunting: 'He is charming and sociable. Women like him but he is a beast inside, and it is always hard to fight a werewolf.'

The Siberian Times spoke to the sister of victim Tatiana (Tanya) Martynova, 20, whose body was found with Yulia Kuprikova 29 October 1998 by the road in the suburb of Angarsk town. 'It happened 15 year ago but the pain does not go away - it was me who presented Tanya a ticket to go to a concert, and she was killed after attending it', said Viktoria Chagaeva, 46, who owns a beauty salon in Angarsk.

Viktoria Chagaeva (L), pictured with her younger sister Tatiana and mother Lyubov and, below, Tatiana's mother Lyubov with Diana, the daughter Tatiana left behind. Pictures: The Siberian Times

Her sister was married with a small child, and her husband Igor, then 24, was against her going to the concert, but she went with a girlfriend, Yulia Kuprikova, 19. 'On the morning of 29 October, Igor called me saying Tanya had not come back home.

'I got truly scared. It was the first time, she had never done this before. There were no mobile phones at that time, we could only call Yulia's parents thinking Tanya must have stayed overnight there for some reason. But Yulia's parents said she had not come home either.'

They went to the police and were told that they should wait three days before the young women could be listed as missing. That night a shepherd found their naked bodies near Meget, a village close to Angarsk.

'It was 1am when Tanya's husband Igor and I came to the police. We did not tell our mother yet. Igor was absolutely devastated and only repeated - 'She was killed, she was killed'. I was shocked too, but I simply could not believe it and replied - 'what are you talking about?' Later we were told that their bodies were found next to each other, both girls were raped, cut and chopped.

'The experts told us that at first they were killed then raped. My elder brother Oleg went to the morgue to identify Tanya. He had flown from Moscow immediately. He felt sick when saw the body, she was so mutilated. He was almost green when he came out of there - he just could not say a word. I did not dare to go in and look.'

They discovered Tanya and Yulia had gone for a quick drink with friends. Then they were offered a lift by a policeman. 'Only the fact that this bastard was in a police uniform explains why Tanya got into his car. Many people attended Tanya's funeral. It felt as if the whole town was there. Our poor mother lost her consciousness several times, she needed a lot of medicine to cope.

'Igor was in almost the same condition. Tanya's coffin was open, her face was not hurt. He damaged the back of her skull, and her body was heavily cut. Yulia's coffin was closed, her face was cut up and disfigured'.

Tatiana Martynova (right) with a friend Yulia Kuprikova (middle) who they were both killed together. Picture: The Siberian Times

Their mother Lubov 'could not cope with Tanya's death. 'She felt as if she had died with Tanya, life became useless for her. She lived only because she was visiting various mediums one by one, looking for the killer and wasting her money. Nobody gave her any serious information but she kept doing it. She died in 2007 aged 66 from a heart attack. I think her heart could not cope with the pain any longer'.

After Popkov's arrest last year, Viktoria realised she vaguely knew him. They had both been involved in biathlon at the same sports ground.

'I was stuck with horror when I saw the picture of this maniac in the paper and online,' she said. 'My sister's killer was looking into my eyes. I immediately felt as if I'd met him. Looking at him, I could hardly breathe. Some minutes later I looked at him another time and thought - oh my God, I know him! I was so shocked, I even took a knife and cut his face in the newspaper, I needed to let this horror out of me.

'I remember him as a tall slim man, he was always alone, with a slippery and shifty glance. I think such people just must not live. This beast took the life of my sister, who had so many happy years in front of her. I cried a lot that day, but it is time to be quiet and just wait. He will be punished by law and criminals in jail will punish him too, I am sure he will pay for all the murders one day....'

Dmitry, a former police colleague of Popkov's, said: 'When I read about him in the press I literally choked, because I used to work with him and thought I knew him. He was an absolutely normal man. He liked biathlon; once on duty he shot a rapist during an arrest. There was an investigation and he was not punished, the chiefs considered he had taken fair action'.

Another ex-colleague Nikolai said: 'I used to work closely with him for 5 years. He knew lots of jokes and stories, and could be soul of the party'.

Road near the village of Meget with Tatiana and Yulia's bodies were found. Picture: The Siberian Times

Angarsk psychiatrist Alexander Grishin said: 'There are two groups of maniacs - organised and non-organised. Non-organised maniacs are easy to catch, their crimes are quickly solved - they are people with psychiatric pathologies, who live in their own world, they are hiding from people, often untidy.

'Organised maniacs - Popkov is a good example - are people with high mental abilities, socially adapted, often with families, they find convenient jobs

which secures them and gives time for crimes. It is a hard job to catch such a maniac, it is hard to spot such a person, even police enrolment tests are not good enough for it. The fact that only drunk women attracted him could be the result of his childhood problems and associations - his mother used to drink alcohol and often abused him.

'Maybe in his childhood other drunk women abused him too, and all this affected his behaviour later in his adult life and led to such horrible consequences.'

Among Popkov's other victims were Maria Molotkova, 20, who worked at a water pumping station in Angarsk. She was found dead in the forest after going missing on 17 August 1999. All the workers from local water supply company came to her funerals. A few days earlier, on 12 August, a beheaded body of a woman was found - with six knife wounds. Her remains were discovered in a rubbish container in Angarsk. She was a medical student.

Her head was found in a rubbish container in a different district. Marina Lyzhina, 35 and Lilia Pashkovskaya, 37, were buried in closed coffins on 8 June 2000. The Russian tradition is for coffins to be open at the graveside so relatives can say a final farewell. But they had been too severely disfigured, like many of Popkov's victims.

Victim Yulia Kuprikova, killed by the 'Wednesday murderer'. Picture: The Siberian Times

Marina and Lilia were friends and worked the same shop. On 2 June they went to see Marina's sister.

At midnight they started to go home. At first they wanted to order a taxi but then changed their minds. It was a plesant summer night, and they decided to walk. On 5 June, their bodies were found in the forest near Veresovka village. Marina had a 14 year old daughter, Lilia had two children, a 12 year old daughter and three year old son.