News of a secret police register in Sweden containing the names of 4,000 people, most of them Roma, has tarnished the Swedish reputation for tolerance and resulted in anti-Roma prejudice being described as the last "acceptable racism" in the country.

"When I saw this I got scared," says Adam Szoppe, a journalist with Swedish national radio.

He's talking about the story which was splashed across the front page of one of the country's leading daily newspapers, Dagens Nyheter, in September, which revealed that a police force in southern Sweden had compiled a register of more than 4,000 names, most belonging either to members of the Roma community, or to people closely connected with it.

More than 1,000 are the names of children, some of them as young as two. Others belong to people who have been dead for many years.

The police have defended themselves by saying the register was drawn up to help them fight violent crime in southern Sweden, and that despite the register's title - Kringresande or Travellers - it had no ethnic basis or intent.

It is illegal under Swedish law to process information about someone based solely on their ethnicity.

The next day, Dagens Nyheter published further details, including a photograph of part of the register with the details blurred out, but enough of it was legible for Szoppe to recognise his home address.

"And there you could see written 'girl born 2010' and where I live there are only three Romany families and I am the only one with a three-year-old daughter," he says. It turned out that Adam Szoppe, his wife, and three of his four children were on the police register.

The reporter who broke the story, Niklas Orrenius, describes discrimination against the Roma as "the last acceptable racism in Sweden", though the revelations have caused widespread shock and anger across the country.

"I have met many Roma people on the list," he says, "and they said they don't believe the police is preparing ethnic cleansing or something like that, but they're scared because this is a state-controlled register of thousands of Roma, and who knows who'll be in charge of Sweden in 20 years and what they will use it for."

The former leader of Sweden's liberal Folkpartiet, Maria Leissner, says the register represents a "hate crime".

She led a government-backed investigation into the treatment of Roma which concluded in 2010 that "Roma today are almost completely excluded from mainstream society."

'I don't care if I'm on the register' "I don't know if I'm in the register, and I don't really care," says Ralf Novak Rosengren, a Roma musician. "But when I saw it in the newspaper, I was very afraid." Rosengren is one of the leading figures behind the Nordic Romani festival that was held for the second year in Stockholm at the end of November. "We wanted to celebrate the first arrival of Roma in Sweden 500 years ago in 1512," he says. "We've been afraid to show ourselves up to now because we have been so afraid of discrimination." Rosengren says the police register raises the spectre of the 1940s when Roma people were victimised by Nazi Germany because of their ethnicity. "This shows that people are not learning from history," he says. "Outside in Europe there are a lot of right-wing people, fascists, people like that, and that's what we're afraid of."

The report also said that about 80% of Roma were unemployed and the majority of Romany children did not even complete primary school.

"When I was about 13 and went to seventh grade they were asking me, 'Why are you going to school, what do you think you're going to be when you get older? You're a Roma, a gipsy,'" says Adam Szoppe, who reports for Swedish national radio's Romany broadcaster, Radio Romano.

"The teachers did not believe in me, even when I went to high school. They would ask me if I can dance and sing and they didn't believe that I could graduate from school like other people."

The Roma first arrived in Sweden 500 years ago. The population today is estimated at some 50,000, but no-one knows for sure because many Roma are reluctant to acknowledge their ethnicity publicly.

Image caption The Nordic Romani festival in Stockholm is in its second year

One woman was apparently desperate to find out if she was on the police register but afraid to ask because if she did, then the police would know she was Roma.

It is not that long since Roma children faced being forcibly removed from their parents - the last known case was in 1975 - and Roma women were subjected to forced sterilisation.

But there is nothing exceptional about Sweden's treatment of Roma, according to Amnesty International, which says they suffer systematic and widespread discrimination across Europe.

"Roma are pushed to the margins of society due to discrimination in relation to housing, employment and education… and used as scapegoats for wider societal problems," says Nicolas Beger, Director of Amnesty International's European Institutions Office.

Image copyright Dagens Nyheter Clearly it's their Roma identity which is the common denominator here Peter Wolodarski , Dagens Nyheter editor

He called on the European Commission to step in to halt what he termed "this continuing cycle of violation of fundamental rights within the EU".

The police force in southern Sweden who drew up the register continue to deny that there is an ethnic basis to it, or that the word "kringresande" or "traveller" has any ethnic connotation.

They began to compile the register, says Stefan Sinteus, head of the criminal investigation department, in order to facilitate a probe into crime related to a "war" between four families near the town of Lund. What began with threats has now escalated to outright violence, involving machine guns and explosives.

"It is our job to fight these crimes," he says.

But Sinteus also now acknowledges that there were too many names in the register, and said they would now create a new register with fewer names. When asked how many exactly, he said he didn't know, but agreed that it might be as few as 1,000 of the original 4,000.

Two officers within that police force are now being investigated for possible criminal offences in connection with the register.

In a recent ruling, the commission that supervises police use of electronic data - known by its Swedish acronym SIN - said the police register breached Sweden's police data act in several ways. They include that:

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•the stated purpose of the register was not clearly defined

•too many people had access to the register

•there was no log to show how the register had been used

"Simply put, we found that too many people were in this register," says Patrick Skogh of SIN.

But SIN said it did not find the register to be in breach of that part of the law that forbids the processing of information about people based solely on their ethnicity.

"The commission found that a lot of people on this register seemed to be of Romany heritage," says Skogh. "However the commission could not find grounds to say that the sole reason for them being registered was that they were of Romany heritage.

"Instead, the reason why they were registered seemed to be some link to criminality."

Dagens Nyheter editor Peter Wolodarski does not accept this.

"We've been in touch with a lot of people in the database and clearly it's their Roma identity which is the common denominator here," he says. "I am confident that when the commission looks at each individual in the register, it will come to the same conclusion as we have."

In Stockholm at the end of November, the head of the Swedish national police, Bengt Svensson, agreed to sit on a panel and take questions from a Roma audience as part of the 2013 Nordic Romany cultural festival.

He appeared regretful, and, while defending the inclusion of children in the register - as potential victims of criminality - he acknowledged that there had been mistakes.

In an interview with the BBC he said that the level of trust among Roma for the police had been at a low level anyway.

"Just now we are under zero," he said. "I think it will take a long, long time before they trust us as they did before."

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