Three babies have died and over six thousands babies have been sickened by contaminated milk formula, China’s health minister said, as the crisis over tainted baby milk spread nationwide. Almost 160 babies are now suffering from "acute kidney failure."

Most babies developed urinary problems, including kidney stones, after consuming Sanlu milk powder for three to six months. Chinese regulators found that the Sanlu-brand milk formula, made by Sanlu Group – China’s premier baby milk brand, was tainted with the chemical melamine. Melamine can cause kidney stones and other organ problems. It is normally used in manufacturing plastic materials.

Health Minister Chen Zhu said he expected the numbers of affected babies to increase as "more and more parents take kids to the hospital," according to the Associated Press.

Yang Chongyong, a vice governor of northern Hebei province where Sanlu is based, said officials in the provincial capital had failed to announce in a timely way this major food safety incident. Sanlu did not inform the Shijiazhuang city government until Aug. 2, despite receiving public complaints about the milk powder five months earlier, said Hebei Deputy Governor Yang Chongyong.

Sanlu’s general manager Tian Wenhua was fired and detained by police Wednesday, the Xinhua news agency said. The political fallout continued Wednesday, with the mayor of Hebei province’s capital, Shijiazhuang, being fired, Xinhua reported. Four other city officials from Shijiazhuang, where Sanlu is based, were fired earlier.