The near riot started out Saturday night with about 20 people trading blows in Malmo and eventually involved dozens with some wielding knives and boards.
Three people were hurt in the melee and a large crowd of people later gathered outside the hospital where they were being treated, The Local.se said. Police cordoned off the area around the hospital to discourage another round of brawling.
The reason for the bad blood between the two clans was not known.
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