Nineteen primary school students in Hunan province were hospitalized after drinking yoghurt allegedly poisoned by a woman who delivered the snack on Wednesday, local authorities said on Friday. Police in Loudi city have detained the 34-year-old woman and suspect that she has a mental disorder. Police said the woman had confessed to having injected rat poison and herbicide into the yoghurt and then delivered the drinks outside a local primary school to students on their way home. Three of the 19 stricken students are in a serious condition, but doctors said their lives are not in danger. Further investigation is ongoing, police said.