How missing person enquiry became one of South Yorkshire Police's biggest ever cases

Gary Allen, aged 47, was jailed for life yesterday for two murders 21 years apart.

The killer’s victims were both prostitutes, with one woman killed in Rotherham on Boxing Day 2018 and another murdered in Hull in 1997.

Jailing him, Judge Justice Goose branded Allen ‘wicked’, ‘extremely dangerous’ and said he held a ‘warped view of women’.

The body of Alena Grlakova, 38, was found in a stream in Parkgate, Rotherham, in April 2019 – four months after she was killed.

Allen’s first victim, Samantha Class, 29, was found on a river bed two decades ago after she was strangled, run over with a car and dumped in water.

Detective Chief Inspector Mark Oughton, who ran the case for South Yorkshire Police, started working on it when Alena was first reported missing and described how it was a difficult investigation from the outset with officers not knowing if the mum-of-four was dead or alive, or even if she was in the UK or back in Slovakia, where she was originally from.

He said another theory was that she may have been trafficked.

The detective said there were also 125 possible sightings of Alena, which all needed followed up.

In total, 232 police officers worked on the investigation, 880 witnesses were spoken to, 1,096 exhibits were seized and 37,624 hours of CCTV were retrieved.

It became a murder probe when DC Richard Stump unearthed voice recordings made by Allen in which he could be heard threatening to harm Alena on the night she vanished.

Allen, who was on the sex offenders register and lived near to where she was last seen alive, initially became a suspect when phone records proved they were acquaintances.

He had previously been on trial over the 1997 murder of Ms Class but was acquitted and walked from court a free man, only to go on to attack two sex workers in Plymouth.

Humberside detectives became involved, re-opened their case and he was charged with the crime for a second time.

His DNA was found on Samantha’s body after she was killed.

Following the discovery of Alena’s body, two police officers travelled to Slovakia to break the news to her loved ones and DCI Oughton personally accompanied some family members, including her children, to lay flowers and light candles at the stream where her body was found.

“It was an incredibly emotional moment and one which will stay with me forever,” the detective recalled.

“It made me more determined than ever to make sure Gary Allen would face the consequences of his despicable actions. Over the coming months, following a tremendous amount of work by the team, everything started to come together.”

DCI Oughton added: “I'm incredibly proud of the whole team - all the hard work is more than worthwhile when we know these families may finally get some closure following the darkest times in their lives. Allen's crimes ripped through two families, and two communities, 21 years apart. I'm glad he will remain behind bars where he belongs for decades to come.”

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