GENEVA, Aug. 30 (Xinhua) -- A large-scale police operation is underway in Aarau, capital of Switzerland's northern Aargau canton, after a shooting in the Schachen district, local police said on Sunday.

Police officers stand guard in Buergenstock near Lucerne, Switzerland, June 22, 2026. (Photo: Xinhua)

One person was killed and five others injured, some seriously, in the shooting near a horse racing track, according to the Aargau cantonal police.

The shooting occurred during "Aarau Rave VOL. 7," a techno event held at the racecourse in the Schachen area, according to local media reports.

Police received the first reports of gunfire shortly after 2:30 a.m. local time (0030 GMT), police spokesperson Pascal Wenzel said.

The unidentified perpetrator remained at large. "Possible motives and the exact circumstances of the crime remain unclear," Aargau cantonal police said in a post on X.

A large area around the scene has been cordoned off, with emergency crews joining the operation. Security has been beefed up beyond Aarau as a precaution.

Authorities have urged the public to stay away from the area and asked anyone with photos or video footage of the incident to come forward.

The swimming pool in Aarau has also been closed due to the ongoing police operation.