Few people are expected to be prosecuted for taking part in May's rioting in Stockholm, with most of the police reports filed no longer being pursued, Swedish police said Monday.
Data compiled by public broadcaster Swedish Radio showed 367 out of 410 preliminary investigations opened by police in the wake of the riots had been discontinued.
So far only one person has been jailed for torching cars during the unrest that broke out in Stockholm's low-income suburbs on May 19. Two others have been fined for drug and weapon crimes.
Identifying those responsible for vandalism was difficult because the events took place at night, and many rioters had covered their faces, Stockholm police spokesman Lars Bystroem told AFP.
"Our main duty when things were at their most hectic was to make sure emergency services were let through to put out the fires," he said
"Technical analysis yield poor results when you only have a burnt out car (to go by)."
Residents had been cooperative but had also found it hard to identify the perpetrators, who were often masked and sometimes travelled from other areas to take part in the riots, according to Bystroem.
Rioters set ablaze more than 150 vehicles and a dozen buildings, shattering Sweden's image as a peaceful, egalitarian society and triggering a debate on the integration of immigrants.
The Scandinavian country has in recent decades become one of Europe's top destinations for immigrants and asylum seekers, both in absolute numbers and relative to its size.
But many of them struggle to learn the language and find employment, despite numerous government programmes.