CHICAGO (CBS) — Six people died early Tuesday in a house fire in rural Ogle County, about 90 miles west of Chicago.

Firefighters responded to the blaze on the 200 block of North Miami Drive in Dixon shortly after midnight, and found the house fully engulfed, according to the Ogle County Sheriff’s Office. At least eight fire departments responded to the scene.

Firefighters determined all six people who live in the home died in the fire. Their names have not yet been released, but sources said they are two parents and four children. Two pets also were killed in the fire.

The Ogle County Sheriff’s Office, Illinois Fire Marshal, and Illinois State Police Crime Scene Services personnel were investigating the cause of the fire.