A lawyer in Hong Kong, who refused to give his name as he could not comment on matters before the court, said it is possible the case will be withdrawn, but it takes time to go through the necessary paperwork.

If the paperwork can't be completed before the scheduled date for a court hearing, Huang can hire a lawyer and win the case, the lawyer said.

Wang Weimin, chairman of the dairy industry association in Xi'an, Shaanxi province, said: "The incident is a big misunderstanding. The customs officers have insufficient knowledge about the regulated goods."

Wang said Hong Kong's limit on baby formula so far has led to foreign brands apparently winning wider market share on the mainland. Many domestic dairy companies have stepped up their quality control and testing capability on harmful substances. But deep-rooted public doubts make these businesses reluctant to compete with foreign brands.

In the first two days of the new limit being introduced, 26 Hong Kong residents, 18 mainland residents and one foreign passport holder were detained, and more than 178 tins of milk powder seized, according to the Hong Kong Security Bureau.

On March 8, two Hong Kong women pleaded guilty and were each fined HK$500 for attempting to carry 1.8 kg of infant powder into Shenzhen, Guangdong province, on March 6.

The new regulation has stirred unease among dairy product dealers in Hong Kong and mainland consumers who prefer buying milk powder in the city because of its high-quality guarantee.

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