No, according to the Danish daily Berlingske Tidende (link in Danish) it was an infamous immigrant gang called Black Cobra that put an end to it because the riots interrupted the gang's drug operations.
Through wiretapping, the police heard that leading members of Black Cobra called a number of youths in [various towns].The police confirms the story:
The message from the leaders was, that the riots was to stop as the police presence on the streets made it difficult for the gang to continue their criminal activities such as selling drugs.
We have followed the activities made by disenfranchised youth in the winter mid-term as we registered that people higher up in the hierarchy were annoyed because it made the police focus on the residential areas, says Kim Kliver.
You gotta love the new speak in Klivers statement. Kliver is a police officer and the leader of a national task force, responsible for monitoring and solving gang-related crimes.
Disenfranchised youth. That's one way of saying it. Bullies could be another.
People higher up in the hierarchy. In a gangster movie, that would be "captains."
Residential areas. Ah yes, AKA "ghettos".
Black Cobra is a gang that consists exclusively of second and third generation immigrants. They are slowly but surely taking over the lucrative drug marked that has, up until now, been split between the biker gangs Hells Angels and Banditos after an extremely brutal war in the late 1990'ies. Back then they were blowing each other up with RPG's, fer chrissake. Those are not gangs that will bend over easily, but they have been gradually doing so for the last five or six years, without much publicity. This should tell you something of the potential of Black Cobra.
If they have the power to stop one riot, they can just as easily unleash another, this time much more violent, if they feel the cops are getting too annoying.
We have something to look forward to!
Update: See also Zonka.