China's President Xi Jinping
Two young girls have died after eating poisoned yoghurt left outside their nursery on the orders of a rival school's head, according to Chinese state media.
Police reportedly believe the poisoning was motivated by competition for students between the schools.
The Xinhua news agency says the woman confessed that she injected the yoghurt with rat poison and asked a man to place it with notebooks on the road to the rival nursery school in Hebei province's Pingshan county, reports Sky News.
The girls' grandmother is believed to have found the books and yoghurt and taken them home on April 24.
The children suffered convulsions and were found "foaming at the mouth" after drinking the yoghurt.
One of the children, whose ages were not given, died before reaching hospital, while the other died later.
Xinhua said police detained the woman and the man.
Many children in the Chinese countryside are cared for by their grandparents because their parents have migrated to cities to find work.