Chinese state media say the number of children hospitalized after drinking milk products contaminated with an industrial chemical has risen to nearly 13,000.

China's official Xinhua news agency said nearly 40,000 infants who drank tainted baby formula have been treated by hospitals on an outpatient basis. Xinhua, citing China's health ministry, said 104 of the children who doctors hospitalized are still in critical condition.

In the first reported case outside mainland China, health officials in Hong Kong confirmed Saturday that a three-year-old girl has developed severe kidney problems. The girl became ill after drinking a contaminated Chinese-produced milk beverage for the last 15 months. Hong Kong authorities have also found a small amount of melamine in Chinese-made Nestle brand milk.

A World Health Organization official said Sunday that Chinese government agencies failed to communicate with each other at the start of the scandal.

The official, Western Pacific director Shigeru Omi, said the Chinese government needs to improve its laboratory testing facilities and reporting systems. But he said China is moving in the "right direction" by recalling products and stepping up food safety inspections.

Four children have died after drinking baby formula contaminated with the chemical melamine that was produced by Chinese dairy manufacturer Sanlu group. Chinese investigators have found the same chemical in the milk products of at least 22 other companies. Melamine can cause foods - such as watered-down milk - to appear to be higher in protein.

Bangladesh, Brunei, Burundi, Gabon, Malaysia, Singapore and Tanzania have banned milk products from China. Burmese authorities are promising to seize and destroy Chinese milk products.

Eighteen people have been arrested in connection with the milk scandal. A group of lawyers offering legal aid to families affected by the scandal is pushing for the government to provide compensation.

Some information for this report was provided by AFP, Bloomberg and Reuters.