The government has obtained information about which formula brands parallel traders are stockpiling, the health minster says. Dr Ko Wing-man's announcement yesterday comes after an investigation by the South China Morning Post determined hundreds of boxes of various formula were being hoarded at a popular staging point, the Advanced Technology Centre in Sheung Shui, where parallel traders collect and drop off their products. Ko said: "We have obtained information from the Security Bureau and Immigration Department on specific brands that have been chosen for stockpiling at the market." Traders hoarding formula has been a problem for years, with some Hong Kong mothers finding their favourite brand often out of stock. The government is advising retailers against co-operating with the traders. At the Sheung Shui market, hundreds of people carried carts and trolleys in and out of the building all day. Boxes containing formula along with food and diapers were piled up in a storage area and along a corridor. Friso and Mead Johnson - famous brands that are now hard to find in the city due to shortages - were stacked among the dozens of boxes. Friso said it was producing one million tins of milk formula for the Lunar New Year - double the supply last year. Abbott said it increased this month's supply by 50 per cent more than December's. Mead Johnson said the company might consider asking distributors to cut supply to retailers if the businesses were found to be engaging in unfair selling tactics, such as raising the price to an excessive level. It will put an extra 540,000 tins on the market to meet the higher demand.