China's melamine scandal broke out in July, when several children were diagnosed with kidney stones after eating contaminated milk products. The first melamine-tainted eggs were discovered in October.
Hong Kong authorities found that eggs containing 4.7 parts per million of melamine, almost double the legal limit, had been supplied from the mainland to local bakeries. Chicken feed is believed to be the source of the contamination. An investigation is underway.
Since mid-July, 290,000 children in China have been found to be affected by melamine poisoning, of whom at least six have died.
Checks carried out by Chinese authorities revealed that several companies added melamine to their milk to make it appear rich in protein. It was also found in non-dairy products, including those of global brands, produced in China.