The small town of Stromsund, on the edge of the Arctic Circle in Sweden's far North, is normally a quiet place. Half buried under snow for much of the year, life is generally ordered and comfortable, its people calm and civil.

But on one day in 2012 that peace was shattered. One of the town's residents, a refugee from the Central Asian state of Uzbekistan, was gunned down in a stairwell at his home.

As the startled local police rushed to respond, it soon became clear that this was no random act of violence or a crime carried out for the usual motives of money or passion. Although the intended victim survived the shooting - he is still in a coma today – investigators realised the attack bore all the hallmarks of a professional assassination attempt. And it was not difficult for them to work out where responsibility might lay.

The victim was a Muslim cleric - an Imam - and in his own way a truly remarkable man. Since the mid-1990s, Obidhon Nazarov had been Uzbekistan's most popular religious leader, followed by tens if not hundreds of thousands of people. But he was also a man on the run. By the time he was shot, he had been hunted by the Uzbek security police for almost two decades. His crime - at least in the eyes of those who sought to kill him - had been to become a symbol of opposition to a regime that is renowned for its brutal response to those who stand against it; especially those whose religious views do not satisfy the country's notoriously dictatorial president, Islam Karimov.

Steve Swerdlow, from Human Rights Watch (HRW), explains: "Uzbekistan is known for being one of the most repressive governments and states in the world. It's distinguished by a uniquely atrocious human rights record – outright government persecution of people who are viewed as suspicious because they practise their religion outside of strict state controls. So that can mean carrying a Quran in your pocket. It could mean wearing the hijab. It could mean wearing a long beard if you're a man. And this causes many to flee out of sheer fear for their lives."

Obidhon Nazarov had been one of those forced to escape. " Nazarov was a charismatic individual, an imam, a learned man, a young man," said Swerdlow. "He used an Islamic lens to shine a light on some of the most pressing questions in this society: How does one live a moral life? And what Karimov saw, not only in Nazarov but other charismatic Imams, was a potential power base, a way to move people to mobilise people potentially against him. He was essentially viewed as an extremist, and treated as a mortal threat."

During the 1990s, speaking to thousands in his mosque in Uzbekistan's capital Tashkent, Nazarov had openly accused the Karimov regime of having kidnapped and killed other imams who had criticised the government. He preached non-violence and was fierce in his denunciations of any one who suggested a more physical response to the government, but he did not hold back from pointing out the abuses that he saw all around him. It was enough to bring the wrath of his enemies down on his head. In 1998, he was tipped off that the secret police were about to arrest him and he managed to get out of the country with his family. After hiding in neighbouring Kazakhstan they were forced to move again and again out of fear that Karimov's agents were on their trail. And then finally Sweden granted them political asylum and they found refuge with other Uzbek exiles in the country's far north.

But if they thought they were safe in Stromsund, they have now been forced to think again. As Swedish police discovered, Karimov's men had been able to track them down without too much difficulty. Using phone and computer records, bank transfers and security camera footage, investigators soon uncovered the identity of the hitman - who carried an Uzbek passport - and two other Uzbeks who were living in Sweden who had helped him. Fees for all three had been paid into bank accounts in Uzbekistan.

But despite this and other clear evidence, two years on nobody has yet been convicted for the attempted murder. The hitman left the country soon after the shooting and is now believed to be in Russia. So far the Kremlin has refused all requests to extradite him. And without their main suspect, Swedish prosecutors have had no choice but to let the others go.

So what now lies in store for the charismatic young Imam, lying in a coma in a Swedish hospital attended only by his family who were forced into exile alongside him? As filmmaker Michael Andersen discovered for this People & Power film, the Imam's family and other Uzbek political and religious exiles are living in constant fear. They had felt safe and secure in a country known for its tolerance and kindness, but the shooting and the apparent inability of Swedish police to bring the culprit to justice has left them feeling unprotected and terrified of what President Karimov's men might do next. The dictator has a long arm and he seems to reach out for his opponents with impunity. Ao they ask themselves, who will be next?

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