Police in a Phoenix suburb say three people, including a teenager, were killed and five others were injured after a shooting outside a crowded concert and car show.

The fatal shooting Sunday night at a restaurant and event venue in Glendale, Arizona, was an “isolated incident that involved individuals that were known to one another,” the city manager’s office said in an update Monday.

A shooting that erupted at a restaurant in Glendale, Arizona, killed three people and injured five others, authorities said.