Swedish police said four people were rushed to hospital but the seriousness of their conditions is not yet known.
Multiple shootings at different locations broken out in the center of a town on the southern coast of Sweden on Thursday night, and police were reporting several people injured.
'We are blocking certain areas and will conduct an investigation.
Police say the violence is not being treated as a terrorist attack and officers are continuing to hunt for the gunman.
The police spokesman, Fredrik Bratt, added that there were "at least four" victims who suffered "suspected gunshot" wounds.
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4 people were injured in city of Trelleborg in Sweden.
Aron Tydén told local newspaper Expressen: 'I was at home at my computer when I heard a loud bang.
"There were many shots".
A huge police operation has been launched and the area around where the drama unfolded has been cordoned off. "We saw someone running outside", an eyewitness told the Swedish publication Expressen. Forensics team and a canine unit have also been dispatched to the scene of the incident.