Chicago — Fire officials continued to seek the cause of a weekend apartment blaze that killed seven people, including four children.
Assistant Fire Marshal Ron Opalecky of the Chicago suburb of Cicero said the blaze was believed to have started at a back porch early Sunday.
Asked if it had been intentionally set, he replied, "Nothing has been ruled out."
Investigators have talked to witnesses and are checking electrical equipment as well as heating and air conditioning units.
Asked if smoking may have been the cause, he said, "Because of the extensive damage, it's going to be hard to conclude anything like that. The back porch is totally gone. There's nothing there whatsoever."
The bodies of two victims, both adults, were found at the ground level of the porch area, he said. The other five, including all four of the children, were in the attic.
A single stairwell in the second-floor kitchen appeared to have been the only entrance to the attic, Opalecky said. Relatives said flames shot up the stairs and cut off escape.
Opalecky said smoke detectors were sounding when firefighters arrived, but it was unclear whether there were any detectors in the attic.
Relatives identified the dead as Byron Reed, 20; his girlfriend, Sallie Gist, 19; their sons Rayshawn Reed, 3, and Byron Reed, 3 days old; Gist's brother and sister, twins Elijah Gist Jr. and Elisha Gist, 16; and a family friend, Tiera Davidson, 18.
One firefighter, Dennis Sean Ahrens, 39, was hospitalized in "guarded but critical" condition, fire officials said.