DNA nails killer - probably

"Last Thursday morning the telephone rang at the home of Helén Nilsson's parents. It was the police. 'We've probably got the man who killed your daughter.'"

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So began DN's coverage of the story that has dominated this week's front pages, the rape and murder of a 10 year old girl in the southern Swedish town of Hörby.

Last week a 52 year old man was arrested for her murder, after DNA profiling matched him to a tiny sample of semen found on her body. But what makes the case so significant is that the murder took place 15 years ago.

On 20th March 1989 Helén had arranged to meet her friends outside a shop in Hörby. She never arrived. For six days Sweden held its breath while police searched for her, but on 26th March a member of the public found her naked body in a plastic bag in a forest 25km from her home. It had been concealed by a mound of stones.

As well as the semen, forensic investigators took hairs, both human and from a dog, from the body and concluded that after being imprisoned for several days Helén had been beaten to death with a blunt instrument.

Over the following months and years a number of suspects were questioned, including a Danish rapist, a serial killer and a pair of cousins who were held for almost two months, but none were prosecuted.

The semen sample remained frozen at the State Criminal Technical Laboratory in Linköping. But last year it was sent to an English organisation, Forensic Science Service, which had developed a completely new method of analysis. In the autumn, Forensic Science Service returned a full DNA profile of the man the semen came from.

Armed with this new evidence, police began trawling their files for suspects and came up with 29 men whose DNA they wanted to compare with the profile. Among them was the 52 year old, who had only been on the fringes of the investigation for the last two years after renewed media interest had attracted some new tip-offs.

He willingly provided a sample of his DNA and was among the last five suspects to be tested. Last Wednesday Skåne police were informed that his DNA matched the profile and at around 10pm he was arrested at his home in Småland.

In a press conference the following day, police chief Henrik Malmquist was confident that they had got their man.

"According to the English company which carried out the DNA profiling, the chance is one in fifteen million that it wasn't the 52 year old in custody who left traces on Helén Nilsson's body."

Nevertheless, the man denied the murder.

If at the time of his arrest little was known about the man except his age and where he lived, the days which followed brought a surge of revelations. And the undercurrent was that it was more than just his DNA profile that labelled him as the killer.

At the time of the murder the man was living in the Hörby area, but in 1990 he moved to Småland. He became known as a loner who was often seen with his dog. He had been in trouble for shoplifting and, according to Svenska Dagbladet, "causing a highway obstruction", after laying nails and screws in a road.

He has a 13 year old son who lives with his mother in another country and he has been campaiging to be allowed to see him. Last year he had a letter about his case published in Expressen and he is said to have sought help from former Prime Minister Carl Bildt.

Monday's tabloids declared that the man was considered to be a suicide risk and was not being given access to newspapers, television or radio. The stories that emerged throughout the rest of the week perhaps justified that decision.

Tuesday focused on the man's somewhat vague links with a man who made pornographic films but Wednesday's headlines will be considerably more damaging. According to a new witness the man is said to have told colleagues that the youngest girl he had had sex with was nine years old.

On Thursday the investigation turned to the man's summer cottage, following an anonymous tip-off to the newspaper Skånska Dagbladet. The caller apparently provided precise details of where blood-stained clothes and a dead dog were buried. Thursday's Aftonbladet reported that police had found "important evidence", including dog hair, in the cottage.

The paper also revealed that the 52 year old is now a prime suspect for other unsolved murders of young girls in the south of Sweden. Top of the list is the murder of 26 year old Jannica Ekblad, who was also killed in 1989. She was found in the same type of plastic bag and with traces of the same type of dog hair as Helén Nilsson, and police have long suspected that the same person killed them.

As for the Helén Nilsson case, police chief Henrik Malmquist would not go so far as to say that it had been cleared up.

"But we have never before been so close to solving it," he said.