On Sunday, a man was killed in Hässelby farm in the 41st fatal shooting so far this year.

There have now been almost twice as many murders using firearms in Sweden as at this time last year.

At the same time, it is only in 10 of the murder investigations that one or a few suspects are detained.

The fact that there are so few people in custody is due to the fact that this type of gang-related crime is difficult to solve and it usually takes a long time before someone can be arrested, says Sven Granath, criminologist and analyst at the police in SVT's Aktuellt.

- If a case is solved, you may not know until a year or two later, unlike other murders where you often have a person arrested immediately.

Here you can spy quite a lot and collect evidence.

Many known suspects may have fled abroad.

This type of deadly violence is difficult to explain, unfortunately.