The chairwoman of a Chinese diary company has gone on trial over a tainted milk scandal that has killed at least six children and made thousands ill.
Tian Wenhua, 66, former general manager of the now bankrupt Sanlu Group, pleaded guilty to charges of "producing and selling fake or substandard products", state-run Xinhua news agency said.
New Zealand dairy giant Fonterra has a 43% stake in the now-bankrupt Sanlu.
Ms Tian appeared with three other company executives at a court in Shijiazhuang, capital of northern Hebei province on Wednesday. It was unclear whether they could face the death penalty.
Executives at Sanlu failed to report cases of Chinese children developing kidney stones and other complications from drinking milk adulterated with melamine for months before the scandal broke in September.
Melamine, an industrial compound used in making plastic chairs, countertops, plates, flame retardants and even concrete, has been added to food to cheat nutrition tests due to its high nitrogen content.
Another 17 people involved in producing, selling, buying and adding melamine in raw milk went on trial in the last week.
At least six children have died and more than 290,000 made ill from the contaminated milk, prompting massive recalls around the world.
Ms Tian told the court on Wednesday she learned about the tainted milk complaints from consumers in mid-May, the official Xinhua news agency quoted her as saying.
The company set up a working team led by Ms Tian to handle the case, but did not submit a written report about the milk powder to the Shijiazhuang city government until 2 August, she said.
The Shijiazhuang government did not report the case to higher government authorities until a month later, prompting speculation authorities sought to avoid a scandal upsetting Beijing's Olympic Games in August.