Electrical workers had disrupted service to a part of the Mississippi County community to swap out a transformer. Power was restored about 2:30 a.m. Thursday - about the same time that neighbors reported the fire.
Burn patterns indicated that the blaze started near a space heater, said Lt. Bryan Crites, a sheriff's department investigator. The power company is also looking into the blaze.
``We have our own investigators working on it to ensure that all of our equipment was proper,'' said Larry Hellums, president and chief executive officer of the Mississippi County Electric Cooperative.
``We don't see a direct correlation (between the maintenance and the fire). The timing is certainly being looked at as to why the space heater would start a fire so quickly,'' Hellums said.
The fire killed Tena Lyvonne Rinehart, 39; Tonya Tomblin, 17; Brian Keith Rinehart, 14; and Robyn Rinehart, 11. The three younger victims all attended Manila schools.
``We consider it a great tragedy, and it's a loss because they all added positively to our school atmosphere and environment,'' Superintendent Pam Castor said.
Tena Rinehart's husband William was working at a Wal-Mart in Blytheville at the time the fire broke out. Store employees took up a collection for Rinehart and will attempt to make sure he has food and clothing.
The power company shut off power to about 650 customers about 11:30 p.m. Wednesday. Officials at the cooperative had only learned Wednesday morning that they could install a transformer that night and did not have time to inform customers about the planned outage.
Temperatures dipped below freezing Wednesday night.
The Manila Volunteer Fire Department said the Rineharts did not have a smoke detector in the home.
