At least five children, including a 10-month old baby, are being treated in the Children's Hospital, Guangzhou after eating food tainted with prohibited rat poison. A duty officer at the hospital said a four-year-old girl had died at noon on Saturday. The baby and a one-year-old girl, who was relying on a life-support machine, were in critical condition. A source in Guangzhou said rat poison was found in the stomachs of the children, including the baby who was still being breast-fed. The children had fallen ill at different times and in various parts of the city over the past few weeks. The source said at least a dozen people had died since unauthorised use of rat poisons was banned by the central Government in 1989. A two-year-old boy was transferred from Zhengcheng to the Children's Hospital after eating a home-grown papaya. His uncle admitted he had been using a prohibited rat killer on his farm, a source said. The four-year-old who died on Saturday had been taken by her parents, migrant workers from the Guangdong city of Xinhui, to the Guangzhou hospital.