Fire officials say a massive blaze that killed a woman and three children and spread to four other houses early Wednesday may have been caused by space heaters.

Officials confirmed the deaths of a 51-year-old woman and three children — two boys, 10 and 5, and a girl, 8 — in the early morning fire.

Family members say eight people in all were living in the Highland Park, Mich. house, which did not have heat.

As the fire spread to nearby houses on the residential street, three homes burned to the ground and two were gutted.

The neighborhood, one block from an urban freeway, consists of older, two-story homes. Officials say many are vacant.