It does not matter if the image quality is poor, send in anyway - so the police in Lund express themselves in the Facebook post.
With the help of police technology, the material could be of importance to the investigation even if the quality is not top notch.
Some pictures and videos have already been received, but now the police hope to be able to shake out more from the public and thus drive the investigation forward.
"We are not in a hurry"
In the post, the police write that they have so far held about forty interrogations and are planning for more.
Seven reports have been made and range from vandalism to attempted murder.
But even there there may be more, the police write:
The work is time-consuming, but at this stage we are not in such a hurry, but the most important thing is to gather enough evidence so that any arrests can lead to lasting prosecution.
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The pictures show how police officers armed with batons and pepper spray try to ward off the quarrel.
Photo: Tobias Nilsson