Two people were hit by shots in the incident at the Gildbrovej road in the town. One person died and the second sustained injuries, media including DR reported.
Police confirmed the fatality via Twitter.
Ifm skyderi i Ishøj: To personer er ramt af skud, hvoraf en er afgået ved døden. En 3. person er lettere tilskadekommen (umiddelbart ikke ramt af skud) #politidk
— Vestegnens Politi (@VestegnsPoliti) September 15, 2019
A third person who sustained mild injury was not hit by the shots.
The shooting, which was confirmed by West Copenhagen Police late on Sunday, is being treated as part of an organized crime-related conflict.
Armed police were present in the area in large numbers until around midnight on Sunday, according to DR’s report.
Photos from the scene showed a car with at least one smashed window and several bullet holes in the driver’s door.
Police have since urged the public not to spread on social media a video which has been reported to show the shooting.
Witnesses with information which might be relevant to the investigation can contact police on number 114.