TYLER – The Smith County Fire Marshall’s office has not been able to find the cause of a that killed a mother and her daughter last month. Killed were Alejandra Mayorga Chavez, 66, and Herlinda Beltran, 35. The February 12th fire was reported shortly after 5:15 that morning in their mobile home in Chapel Hill. Assistant Fire Marshall Chad Hogue said his office and the ATF, have completed their investigation into the fire. He said, while the cause of the fire is undetermined, foul play is not suspected.