Stockholm, Sweden (CNN) -- A suspected serial shooter is keeping a city in southern Sweden on edge. Police say as many as 15 shootings in Malmo over the last year may be linked to a single perpetrator who is targeting immigrants living in the city. Investigators have no suspects. The shootings have all been well planned, under the protection of darkness and at places familiar to the shooter, according to CNN's Swedish affiliate TV4, citing police. Several of the shootings have occurred in recent weeks, police say. On Thursday evening, two immigrant women were wounded when shot through their apartment window.
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Shooter targeting immigrants, police say
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15 cases could be linked to unknown shooter
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Attacks have happened in southern town of Malmo
The shootings also bring back memories of @placeholder's "Laser-man," a shooter who was targeting immigrants in Stockholm in the 1990s with a laser-aimed rifle.