A fast-moving fire early Friday killed a retired farmer and critically injured his wife in their ranch home in the Genesee County community of Byron.

Warren Leaton, 90, a lifelong Byron resident who was a dairy and cash-crop farmer, was discovered dead on the kitchen floor of the smoke-filled home at 6920 Caswell Road shortly after Byron firefighters arrived just after 2 a.m., Fire Chief Charles Durkee said.

Noreen Leaton, 84, a former Byron town clerk, was alert and talking when firefighters rescued her from a breezeway in the home, Durkee said. She remains in critical condition in the intensive-care unit of United Memorial Medical Center, Batavia.

Officials said frozen rain, a lack of nearby water sources and a fallen power line hampered firefighting efforts. Firefighters from several area companies battled the blaze, which was brought under control in about an hour. Genesee County authorities were alerted to the blaze shortly after 2 a.m.

Durkee said the cause of the fire, which originated in the living room, remains under investigation but does not appear to be suspicious.

The house was declared a total loss.

The investigation is being conducted by the Genesee County Sheriff’s Office, state Office of Fire Prevention Services and Genesee County’s Emergency Management Office