Waving their families goodbye, the four men were in high spirits as they loaded their jeep and set off on a much-anticipated adventure holiday.
Their destination was a land from another time, a largely unpenetrated corner of eastern Siberia roamed by bears and wolves, where sightings of yeti-like beasts are not uncommon and only the hardiest of explorers dare to tread.
What happened next to the four Russian travellers is a mystery only just beginning to yield its secrets. And the story of their four-month ordeal has gripped and appalled their country in equal measure.
Baldly, the facts are these: Two of the men returned alive, one is still missing, while the fourth man – 44-year-old Andrei Kurochina – was found dead in strange circumstances.
At first it was assumed he had simply perished in the extreme cold. But then the shocking truth began to emerge. Police discovered he had been cannibalised and that his flesh quite possibly was eaten by his best friend, Alexei Gorulenko, and fellow adventurer Alexander Abdullayev, to keep themselves alive.
Abdullayev, 37, insists they ate Kurochina only after he died from natural causes. But the police suspect otherwise and have launched a murder investigation.
At her home in Volsk, southern Russia, Kurochina’s widow Olga is struggling to make sense of it all, while across town her husband’s friend Gorulenko is back with his family, recovering from his ordeal, and saying nothing.
‘I am in contact with his wife but not him,’ said Olga. ‘Her Alexei is alive – but, believe me, she is suffering no less than me.
‘I can’t bring myself to speak to Alexei yet. I’m not ready to hear what he can tell me and he can’t open up to me. I find it too painful to even think what I feel about him now.
‘Andrei and Alexei were close friends for almost 20 years. They were passionate fishermen and often went away together.
‘This time they were with two others who I didn’t know and this worried me. But I knew Andrei was with his best friend so I thought everything would be all right, that they would look after each other. We could never imagine it would end like this.’
It was from Abdullayev rather than 35-year-old Gorulenko that the ghastly truth emerged following the police discovery of human remains.
He, like Gorulenko, had initially denied cannibalism, but taken back to the scene by police helicopter, the confession spilled out of him. ‘We didn’t kill him.
‘He died from the cold after getting a leg injury. He was frostbitten and froze to death. Only after that did we start eating him, to survive.’
Explaining that he and Gorulenko used an axe to hack apart his frozen remains, he added: ‘We needed protein. We cut his flesh from the bones and ate it and it helped us to survive for ten days.’
It was in July, at the height of one of Russia’s hottest summers on record, that Gorulenko and Kurochina left Volsk and began a 4,300-mile drive in a Soviet-designed UAZ off-roader.
Fanatical about fishing, they had ventured many times along lonely rivers together, but never had their destination been this remote, nor so ambitious.
The desire to undertake such adventures is ingrained in many Russians and Olga expected them to be away ‘for one month – or two at the most’.
Both men were fairly well-known locally. Part of the new bourgeois class that has risen under Vladimir Putin, they worked as senior managers in cement plants in the region around Saratov, birthplace of Roman Abramovich.
It remains unclear how, when and why they chose unemployed carpenter Abdullayev and 47-year-old welder and former gold miner Viktor Komarov – the man who is still missing – as the other members of their expedition.
This pair certainly had a degree of local knowledge, both being from villages close to where the quartet began their fishing odyssey.
But Komarov’s involvement is the reason that some are beginning to suspect that there was another element to the trip – that in fact its primary purpose was gold prospecting.
On August 8 all four set off from Pervomaiskiy village, initially going north some 185 miles via the hamlet of Dipkun to the Sutam River in Sakha, a region home to Russia’s diamond industry.
It is also the location of the sinister Road of Bones highway, built by inmates of Stalin’s forced labour camps – many of whom died in the process.
‘I heard from Andrei for the last time by text on August 10. He said the mobiles wouldn’t work any more as it was too remote,’ said Olga. ‘I knew he would be out of touch for weeks.’
They had some warm clothes but not winter gear, as they did not expect to stay in the taiga, Siberia’s vast forest, for winter.
In their luggage was their fishing equipment, two hunting rifles and traps to catch hare. They also had ‘a huge pile of money’.
By around August 20 they hit trouble. The off-roader broke down and Gorulenko and Abdullayev went back to Pervomaiskiy on foot before hitching a ride on a cargo train to pick up spare parts.
They returned to the others with the vehicle fixed. But a month later catastrophe hit as the group forded the swollen Tarynnakh River.
The vehicle stuck and as the men tried to free it from the fast-flowing waters, it upturned. It sank with the loss of all their possessions except the guns, ammunition and money.
All four took refuge in a remote hunting lodge, which they used as a base for a number of weeks, until they exhausted its food supplies.
What happened next is sketchy but it appears they did not perceive themselves in great danger.
They did not seem in any rush to escape from the taiga, despite losing their fishing tackle and the vehicle, in which they had often slept.
During this period they encountered a number of hunters who had vehicles and walkie-talkies. At least one let them use his satellite phone.
‘Alexander called his mother by this sat-phone in early October and said they were all OK and would be out in five days,’ said Olga.
‘But he didn’t mention one crucial thing – that they had lost the vehicle. Had I only known this I would have done everything to get search parties to find them.’
Soon after this call, the winter snows began to fall much earlier than expected. Yet despite chest-high snow they still seemed in no hurry to leave.
Indeed, they could have paid one of the hunters they met to help them as they were not short of money.
Olga admits this is perplexing, but she says only: ‘The weather was against them, everything was against them.
They lost the way at some point and were going in circles. They had no compass. They took a satnav but lost it with the car.’
In a region where hot summer transforms into one of the planet’s coldest winters, with barely a pause for autumn, the temperature was by now dipping dangerously.
At the beginning of October they began walking back towards Dipkun.
They left a note in a hunter’s house saying they had sheltered under the owner’s roof and eaten all his food.
They also left 3,000 roubles – around £60. Their progress back to civilisation was haphazard.
Had they been fit and properly equipped, they could have covered the distance in a matter of days, even with the snow and sub-zero temperatures.
Yet it would be almost seven weeks before two of them were found some nine miles from Dipkun.
In this time it is known all four took refuge in another empty hunter’s shack near the Daurka River, an area described by locals as lonely and macabre.
In recent years, seven dead bodies have been found here.
After Gorulenko and his companion were rescued by helicopter on November 28, he said: ‘Andrei’s leg was aching and he could not walk further, and Viktor was also weak.
‘We agreed to leave them there and go and seek help.’
But his account did not hold water for long. When the police visited the bleak timber house in search of the other two they found it empty.
Outside, they discovered footprints, but none leading towards the river, now covered with thick ice, the obvious escape route.
They led to a pile of snow, hiding frozen body parts, with the flesh hacked off. Nearby, investigators found blood-stained clothing and a wooden stake that might have been a murder weapon.
When they were first confronted with the discoveries, Gorulenko and Abdullayev denied any knowledge. Gorulenko has still not formally confessed.
Asked if he had eaten his friend, he answered: ‘How can you say such a thing?’
In a case beset by mysteries, among its most puzzling was the physical condition of the survivors.
‘Doctors were surprised that they weren’t that bad – not frostbitten, not hurt, their nails neatly trimmed,’ said a rescuer.
‘They were eating and mumbling answers to our questions but they were not keen to communicate.’
The police now find themselves in a peculiar situation over the case.
‘It is right that fisherman Alexander Abdullayev has admitted eating the flesh off his friend’s body and that he did this jointly with Alexei Gorulenko,’ said Dmitri Murashko, who is in charge of the investigation.
However, the Russian criminal code contains no offence of cannibalism. ‘Neither of them are detained, but both are witnesses in a murder investigation,’ he said.
Both men emphatically deny killing Kurochina, or for that matter the missing Komarov.
DNA and other forensic tests take an interminable time in Russia, which means formal identification of Kurochina – and any clues as to how he died – is not likely before March.
Last week Abdullayev’s mother Lidiya, 57, blocked access to her son, saying: ‘He is not back to normal yet.
‘My heart aches just looking at him. He can hardly walk or talk, as if he’s lost and can’t find himself.
‘He’s a shadow of the man who went into the taiga. I know he has spoken of cannibalism and I can’t say any more about it.
‘He told me they could never expect such a snowfall in October. He talks constantly about Viktor but is too weak to go out and look for him.
‘He told me Viktor had said: “You go. I am too weak. I can’t walk any more. I can’t move.”
‘Please understand – this wasn’t an easy decision.
‘In the end they had to move otherwise all of them would have died. They were too weak to carry him out.
‘I can’t be a judge on what happened. Everything is too emotional. The law of the taiga says that the strongest survives.
‘My son proved to be the strongest – but there is terrible heartache and tears in our house since he got back.’
Similarly, Irina, Gorulenko’s 22-year-old wife, said: ‘I hardly recognised him. He was just skin around his bones, no teeth. He’s exhausted. He says he did not eat his friend.’
At first Olga Kurochina simply refused to accept the cannibalism claim. Now, after hearing from the police, and privately from Irina and Abdullayev’s mother, she accepts he was eaten. She still cannot believe it was murder, however.
‘I do not think they killed him. There has to be a motive for murder and I can’t see one,’ she said.
‘Andrei was a healthy man, but maybe because of the cold he got this leg pain that Alexei mentioned.
‘But I still don’t understand what happened next and how he died. It is so hard to put yourself in their shoes. We do not know what metamorphosis the human mind goes through being in such extreme conditions, and nobody knows.’
As she attempts to deal with the tragedy, Olga is finding unexpected solace in accounts of cannibalism by the starving and utterly desperate citizens of Russia’s second city St Petersburg, then Leningrad, trapped under ceaseless Nazi attack during the Second World War.
‘I’m now reading about the Siege of Leningrad,’ she said. ‘To try to help me come to terms with what happened to Andrei.’
But for a miracle reappearance by Viktor Komarov, this bizarre story is unlikely to unravel further before the results of the forensic tests in March or possibly even the snow melt in late May – when the fear is that another set of bones will appear.
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