The bones found at a banana plantation in the northeastern province were of a four-year-old girl who vanished from a Red Cross fair in Muang district on Feb 5, said police chief adviser Jarumporn Suramanee, citing a Police General Hospital forensic report.
The bones found on a hill near a rock crushing plant in Wang Sapung district in the same province were confirmed to be those of a seven-year-old boy, Pol Gen Jarumporn added.
The boy never returned home from a temple fair at Wat Sri Udomwong on Nov 10.
Forensic science experts at the hospital's Institute of Forensic Medicine used DNA samples from the children's mothers to compare with the bones of the girl and boy.
The case of the accused serial killer Nui or Ting Tang, 32, only came to light after the rape and murder of Cartoon, a six-year-old girl, near the BTS Bearing BTS station on Dec 6. He confessed to investigators after his arrest that more children were the victims of his rapes and abductions, including the two in Loei.
Police combed the two locations after the confession and found evidence in accordance with his account.