EAU CLAIRE, Wis. (AP) — Police in Eau Claire say a man who died in a house fire over the weekend was an intruder who was not known to the tenants.

Police and firefighters were called to the fire early Saturday. Firefighters entered and found the body of 21-year-old Jaime Thayer-Vega.

Authorities were called on a report of an intruder and that the home was on fire. Police say a tenant saw an intruder in his home and a physical confrontation occurred. The tenant then notified other people living in the house of the fire, and they made it out safely.

Police say Thayer-Vega was not known to any of the tenants. A preliminary autopsy report says he died of smoke inhalation.

Authorities still don’t know what caused the fire.