NASHVILLE, Tenn. (AP) — Two children initially believed to have perished in a Tennessee farmhouse fire along with their step-grandparents are now considered missing and in danger, investigators said on Wednesday.

The Tennessee Bureau of Investigation said the remains of 9-year-old Chloie Leverette and 7-year-old Gage Daniel were not found and the agency issued an endangered child alert for them on Wednesday afternoon. Investigators said neighbors last saw the children Sunday evening, hours before a fire destroyed the home in Bedford County about a half-hour from Nashville.

The Bedford County sheriff said investigators did find the remains of 72-year-old Leon "Bubba" McClaran and his 70-year-old wife, Molli McClaran.

But the TBI said in a news release that state bomb and arson investigators now report the children were not victims of the fire and their whereabouts are unknown. They are asking for the public to call in tips.

Sheriff Randall Boyce originally said Monday that investigators thought they found three bodies in the home, but one of the remains turned out to be those of a dog.

Family members told The Associated Press that the McClarans were raising their step-grandchildren because they needed a home and described them as generous people who loved their family. Relatives of the McClarans said the girl also used the last name Pope.

Someone passing by the farm saw the home enveloped in flames and called for help.

Law enforcement agents used cadaver dogs to search through the rubble for the remaining bodies. Family members drew a layout of the home for authorities to show the bedrooms.

The fire was very intense and quickly collapsed the walls of the house. Firefighters spent hours battling the blaze and it was still smoldering Monday morning as they searched for the bodies.