Edwardsburg, MI – One man has died and five more people, including three children, were sent to the hospital after a carbon monoxide leak Friday morning in Cass County, Mich.

Andrew Weston of Columbus, 43, was found dead in the basement of an Edwardsburg home near the suspected source of the carbon monoxide, Cass County police say. An autopsy will determine if he died from carbon monoxide poisoning.

Two 5-year-old boys, a 3-year-old girl, a 46-year-old man and a 41-year-old woman were on the first and second floors of the home during the leak, police say. Those five people were taken to St. Joseph Medical Center and Memorial Hospital of South Bend to be treated for carbon monoxide poisoning. A dog in the house was taken to a nearby veterinary care center, where the family will be able to pick it up.

Police believe a heating system in the basement may have been the source of the carbon monoxide. The Ontwa Township and Edwardsburg fire departments also responded to the scene.