HONG KONG - Two food products for sale in Hong Kong, including eggs produced on a Chinese mainland farm and biscuits produced by a Philippine firm, have been found contaminated with melamine, local food safety watchdog said Saturday.

The Center for Food Safety (CFS) said the sample of the Select Fresh Brown Eggs (Extra Large), produced by mainland-based Dalian Hanwei Chicken Farming Limited and sold in 6-piece packs, was found to contain 4.7 ppm (part per million) of melamine.

Under the Harmful Substances in Food (Amendment) Regulation 2008 of the Hong Kong Special Administrative Region (HKSAR), the legal limit for melamine in food is 2.5 ppm.

The website of the producer Croley Foods suggests it is based in the Philippines.

The Center for Food Safety said the two unsatisfactory samples were among 77 samples tested, which included milk, eggs, biscuits, cakes and cake mixes. The results, available on Saturday showed that the rest 75 were all satisfactory.

"We have informed the food trade of the test results and asked them to stop selling the products with unsatisfactory results. We have also sent warning letters to the retailers and the importers concerned," the CFS said in a statement, adding that it would " take out prosecution if there is sufficient evidence."

The center will continue to collect samples of dairy products and products with dairy ingredients for testing. Egg samples will also be collected, with the tests on mainland eggs expected to be completed within next week, the statement said.