A manhunt is under way after one person was killed and five injured when shots were fired at an event in northern Switzerland, local police say.

The force said the shooting happened at a horse racing track where a rave was taking place in the early hours of Sunday.

“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.”

Local media reported that the force was alerted to the shooting around 02:30 local time (01:30 BST).

Swiss DJ Tekibo, who was performing at the rave, described the incident as “heartbreaking” in an Instagram story.

He said he had “lost an important friend” and is “still trying to process what happened”.

“Techno and raves are supposed to be a place for freedom and safety,” he added.

An area around the racing track, the town’s swimming pool and sports field has been cordoned off, with the public urged to stay away.

A large contingent of officers has also been deployed beyond Aarau “as a precaution”, police said. An AFP journalist reported seeing armed officers deployed on the highway up to 30km (18 miles) from the site of the shooting.

Aarau is located some 46km (29 miles) west of Zurich and is home to approximately 23,000 people.

The force asked witnesses to submit photographs and video from the scene.

Images from Aarau early on Sunday showed a heavy police presence in the area, with an armoured vehicle seen blocking a road. Armed police and officers in riot gear could be seen patrolling the streets of the town.

In addition to police and fire officials, the regional disaster response unit (KKE) was deployed, according to broadcaster SRF.

It also reported that a Swiss Army helicopter could be seen surveying the area in the early hours.