Russia's worst serial killer – and the only man two ever be given two whole life sentences – hopes to walk free thanks to Russian President Vladimir Putin.

Mikhail Popkov was found guilty of 56 murders between 1992 and 2017, earning him a second life term in prison in Russia last year. Popkov had already been imprisoned for killing 22 women in 2015 – except he could now walk free by joining Putin's army invading Ukraine.

And if he survives six months on the front line, he will be pardoned for his loyalty, with his crimes wiped from his criminal record, as has been done to countless hundreds if not thousands of other lags over the last two year. But with Popkov, wiping his crimes would impact on the families of his near-100 victims.

READ MORE: Inside Putin's £40m super yacht where Vlad's gymnast lover could be under 'house arrest'

For more mad Russia news, click here.

Mikhail Popkov could be freed to fight in the Russian army
Mikhail Popkov could be freed to fight in the Russian army

The murderer, known as a “maniac” and given the nickname of “The Werewolf”, used a similar tactic for a large chunk of his crimes. He would stop women and offer them a lift late at night while he was off-duty as a policeman in Angarsk, in the south-eastern part of the nation. He killed his victims using weapons including a hammer and an axe.

He would then dispose of their bodies in the woods, at the side of the road and in a cemetery. He was also found guilty of raping 11 of the women.

In interviews with police, Popkov described himself as a "cleaner" who believed he was purging his area of prostitutes. Russia's bloodiest serial killer was later convicted of murdering his 82nd and 83rd female victims.

He admitted to killing 86 woman . . . but is thought to have killed a lot more
He admitted to killing 86 woman . . . but is thought to have killed a lot more

The latest convictions relate to killings in 1995. The 82nd victim was Natalya Zvereva who was sexually attacked and murdered in a Siberian forest.

Married father-of-one Popkov told interrogators he raped Zvereva then “we quarrelled and I murdered her. “I hit her on the top of her head... She fell down and did not show any signs of life.”

He threw her body into a river, he said. The name of the 83rd victim was not disclosed, and he later confessed to three more, bringing his grand total to 86.

Putin could free him, and wipe his crimes from the record
Putin could free him, and wipe his crimes from the record

Police believe Popkov - also called the Angarsk Maniac - may eventually confess to dozens more victims, with one investigator forecasting his macabre murder toll could be “closer to 200”. However, if he is about to walk free, the chances of that happening are now very remote.

A psychiatric evaluation diagnosed Popkov with homicidal mania, “a condition when a person has an irrational desire to kill someone”, reported TASS. Nevertheless, the mass murderer was declared sane.

For the latest breaking news and stories from across the globe from the Daily Star, sign up for our newsletter by clicking here.