Image copyright AFP Image caption Volunteers in Kiev piece together shredded documents found in the former residence of Viktor Yanukovuch

A group of volunteers is painstakingly piecing together shredded documents in the hope of uncovering corruption under the leadership of Ukraine's ousted president, Victor Yanukovych.

Eleven-year-old Dmytro Pynchuk's desk is covered in scissors and pots of glue. He is a dab hand at assembling complicated models and proudly shows off his paper aeroplanes and World War Two tanks.

Now his expertise is proving useful, as he and his parents give up their free time in the evenings and at weekends to piece together shredded documents.

These contain information about stolen assets, offshore accounts, bribes and other secrets that nobody outside the circle of the Ukraine's ousted president was ever supposed to lay eyes on.

Find out more Listen to the full report on Radio 4's Crossing Continents on Thursday 3 April at 11:00 BST or on BBC World Service Assignment at 03:30 BST. Catch up afterwards via the Radio 4 website Catch up via Assignment on the World Service

When Viktor Yanukovych fled his palatial estate north of Kiev in mid-February, his staff attempted to get rid of tens of thousands of sheets of paper by burning or shredding them or by dumping them into a reservoir.

More potentially incriminating documents were found in other parts of the Ukrainian capital. There were several boxes in the sauna of the former General Prosecutor Viktor Pshonka and a raid on the former energy minister's home, Eduard Stavytsky, netted another stash of papers along with nearly $5m (£3m) in cash, 48kg of gold bars and luxury watches and jewellery.

Image copyright AFP Image caption A volunteer scans an image of paper fragments found in the former residence of Viktor Yanukovuch

The documents found in the water were carefully dried, scanned and uploaded onto a new website called Yanukovych Leaks. But the shredded ones need to be carefully reassembled, bit by bit.

The Pynchuk family and scores of other volunteers gather together in donated office space - a basement which was used by Ukraine's Communist Party.

They could be gluing and sticking for several months. But however long it takes, they are determined to help investigative journalists, accountants and lawyers to shed more light on the way business was done when Yanukovych was in power.

Last week they had 40 people a day but in the last few days the numbers have dwindled to 20 a day. More people come at the weekend.

They stick the paper randomly on to sheets so it can be read by the sophisticated computer software programme. Some are long strips and others are short like confetti. Other documents have been torn up by hand.

Image copyright Other

Denys Bigus, a journalist for the ZIK TV channel, is the man in charge of the restoration project. He says: "It's a very long process and will take several more months. The actual work is extremely tedious but people know it is vitally important."

People come to stick the paper together but the atmosphere is very lively, he says - it's like a discussion club. "Last week we had a couple out on a date - they chose to help with the documents instead of going to the movies - volunteering is becoming fashionable in Ukraine these days."

The Pynchuk family are fully committed to their intricate labouring, although young Dmytro concedes it can get a little boring, and it means he can't spend as much time practising his guitar.

We were brought up by our parents never to steal - even the smallest thing Dmytro Pynchuk

His father, also called Dmytro, opens his laptop to show me a sample of the family's painstaking work, which on occasion gives him a headache, he says. It looks rather like an abstract collage - row after row of narrow strips of paper glued onto a coloured sheet. The sheets are then scanned and can be deciphered by a special software programme.

"As you can see the pieces are tiny - like confetti!" says Dmytro who works as a consultant for an international IT firm in Kyiv.

Yet it is sometimes possible to make out signatures, some names and a few words. Dmytro found one document directly related to the former president - a list of his private collection of cars.

"Some of the vintage models - five or six - were stolen from our national film studios", he says. "And you know, we were brought up by our parents never to steal - even the smallest thing."

He adds that on the one hand the ex-president's greed is so outrageous it's almost funny. But then he calls it "stupid and disgusting".

Image copyright BBC Sport Image caption Lilia and Dmytro (son and father) Pynchuk

The shredded documents he and his family have been working on were found at the abandoned Mezhihirya estate and in the underground car park of a downtown office block.

Thirty rubbish bags spewing ribbons of paper were discovered in bins beneath a conglomerate owned by Serhiy Kurchenko. The 28-year-old who became a billionaire almost overnight has long been suspected of being a front man for the Yanukovych family.

Image copyright BBC Sport Image caption Shredded documents linked to Serhiy Kurchenko

Ukraine's new general prosecutor Oleh Makhnitsky has accused Kurchenko's offshore registered companies of trading in oil products using a tax evasion scheme that cost the government an estimated US$1 billion in lost revenues.

I ask Dmytro's wife Lilia, who sells computer equipment, how she feels about these latest revelations. She is silent for several seconds and then, to my surprise, starts to cry.

She explains that she is a part-time fund raiser for a charity which cares for sick children. "Most people can only afford to give us a few kopecks," she says.

"Often we just can't raise enough to treat these poor kids so many don't make it… and then when you see how our president bought chandeliers that cost a hundred thousand US dollars each! I just feel like I want to take this man - and tear him to pieces."

Her son throws his tear-stained mother a worried glance and then makes her laugh by suggesting that Yanukovych should have gone into the shredder along with all his dodgy documents.

Over tea in their kitchen, the Pynchuks admit corruption is not confined to the super-rich. It is endemic at every level of society. Bribes are required for everything from getting a child into school, to applying for a passport to visiting the doctor. Dmytro and Lilia have had to pay many backhanders but they want that to stop.

Image copyright Anastasia Bereza Image caption Documents were fished out of the river and dried

"It's not a good thing," says Dmytro, "because every time you bribe an official you feel you're putting your hand into the dirt - it's an absolutely disgusting feeling".

Lilia is also troubled by the lack of accountability of those in positions of power.

She tells me about her friend who died after a botched caesarean section in 2012. Once the baby girl had been delivered, the obstetrician said he was tired and left without stitching up the incision.

More from the Magazine Image copyright Other A decent commercial shredder can reduce a sheet of paper to more than 400 pieces. That yields a total of 1,276,800 possible two-piece combinations - for one single-sided sheet. So how easy is it to reassemble the pieces? How do you reassemble shredded documents?

"Basically she bled to death - she was left on her own and nobody in that maternity hospital came to help her until it was too late and her face was as white as that", says Lilia pointing at her kitchen wall.

She adds that when the family tried to complain and prevent a similar tragedy from occurring at the same clinic, the doctor warned them he was "very well connected" and told them to leave his office.

In a separate incident, three of the couple's friends were run over and killed by a young businessman in the centre of Ukraine. "He tried to drive off," says Dmytro, "but taxi drivers who witnessed the accident wouldn't let him. Judging from the look in his eyes, he'd taken some kind of drug so they handed him to the police".

But Dmytro assumes bribes were paid to hush up the case because the driver never appeared in court and the families of the victims received no compensation.

"That is what made me go out and join the protests on the Maidan," says Lilia. "This corruption is killing us and I just want to live in a normal country."

Listen to the report from Assignment on the BBC World Service on Thursday 3 April at 03:30 BST or catch up on iPlayer.

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