One person has died and five people are injured after shots were fired at an event in northern Switzerland overnight, local police say.

“The manhunt for the unknown perpetrator is under way,” Aargau Cantonal Police said in a statement. “Possible motives as well as the exact circumstances of the crime are still unclear.”

The force told Swiss media that the shooting took place near a horse racing track in Schachen, Aarau, some 46km (29 miles) west of Zurich.

Local media reported a rave had been taking place in the area into the early hours of Sunday.