STAMFORD, Conn. — The fire chief in Stamford, Conn., is revealing new details about the frantic scene at a Christmas morning fire that killed a couple and three of their grandchildren.

Acting Fire Chief Antonio Conte says the children's mother, Madonna Badger, climbed out a window onto scaffolding and then a flat roof. He says she was screaming for her children and was able to tell firefighters which bedrooms they were in.

Conte says firefighters climbed ladders to the third floor twice, but the heat and flames were too intense and the children were not where they thought they would be.

Stamford Mayor Michael Pavia says foul play has been ruled out. He says preliminary information shows it was just a tragic accident.

He described the cause as "fireplace-related" but could not provide more details.