It was during Monday that several major quarrels flared up in Lund.
A total of about 50 people took part in the riots, where eight people were taken to hospital.
One person was arrested after the riot on suspicion of unlawful threats and assault but was then released on Wednesday.
- It is a very comprehensive investigation, we have a lot of testimonies, pictures and films.
We have had many police officers on site and we see that there is a good investigation situation where we will move forward but it will take time.
There are many things that must fall into place, says Ann-Louise Kämpe.
Formerly known to police
According to the police, this is a family feud between two families who have previously been known to the police.
This will be the same large family network that attracted attention in Gothenburg during, among other things, a major quarrel in Hjällbo this summer.
- There are two families, we see a connection to gang crime and there is kinship within the families.
What is behind the motive is too early to say, says Ann-Louise Kämpe.
"Should keep track of the people"
The police now have a large resource that works with the investigation after Monday's riot.
On Wednesday, the police continued to work with the investigation and with security-creating activities in Lund.
They have also received reinforcements from other police areas in the South region.
- We work very hard with an effort both here in Lund and in Skåne to ensure that there are out there and on site, not least to create security in society but also to ensure crime prevention that it does not happen again.
We must keep track of these people and be out and about in society and we are doing a lot of that right now.