Prosecutors in the Mexican border state of Baja California say the 19-year-old daughter of a Russian woman has confessed to killing and dismembering her mother and her 12-year-old sister, because she thought they were performing witchcraft against her.

An official of the state prosecutors' office who was not authorized to be quoted by name says the older daughter had not yet been detained because police were waiting for a formal arrest warrant.

The alleged culprit has been identified as Anastasia Lechtchenko, but the Russian Embassy in Mexico City could not immediately confirm that name.

The dismembered bodies of the 45-year-old mother and her daughter were found last week in plastic bags at their home in Playas de Tijuana, about a half mile (1 kilometer) from the U.S. border.