In the last ten years, deadly violence in criminal environments has increased.

One example is Linköping, which some time ago suffered a total of six gang-related murders in less than a year.

All murders are so far unsolved.

In a new report, Brå has examined what is required for more such crimes to be cleared up.

Among other things, more investigators who are trained in investigations of serious violent crimes are needed.

- A combination of increased complexity in this type of crime at the same time as this type of investigation increases means that we do not have enough people with this competence.

That's why we sometimes have to borrow resources, says John Andåker, head of the police's investigation section in police region East

"Takes a long time"

At the same time, it will take a long time to get to the problem.

- We have to work strategically to build on the skills and that takes a long time, says John Andåker.

More and more evidence-based

An important aspect to being able to solve gang murders is time.

The study shows that in nearly a third of the cases that lead to someone being sentenced, the convicted person was arrested within 12 hours – in half, the convicted person was arrested within three days.

At the moment, there is no suspect in custody for any of the murders in Linköping.

- We still have good hopes.

But it is undoubtedly the case that the proximity to when the crimes occurred is very decisive.

The investigations are becoming more and more based on circumstantial evidence and the best is always if we can achieve great success in the near term, says John Andåker.

SVT Öst has previously reported on the investigative work in the police region.

Among other things, a "cold case group" is currently missing.

More on that in the clip below:

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- We believe that cold cases belong in the investigation sections of the police regions, says Ravi Ray, head of the investigation unit in the police region East.

Photo: Mimmi Moberg/SVT