Starbucks stopped serving milk in many of its Chinese outlets on Friday as a crisis over poisoned dairy products that have left four babies dead and thousands of others sick spiralled.
The move by the US coffee chain came amid a government-ordered mass recall of dairy products after an industrial chemical initially reported to be only in milk powder was also detected in regular milk, yoghurt and ice cream.
Supermarket shelves across the country were emptied of many products made by Chinese dairy giants Mengniu, Yili and Guangming after the government said melamine had been discovered in some of their regular milk.
Mengniu is one of the main suppliers for Starbucks, leading to the recall in two thirds of the chain's 330 outlets in mainland China.
"Though the milk we received from Mengniu is not included in the contaminated lots, due to the serious nature of this warning, Starbucks pulled all Mengniu milk offerings until further notice," the Seattle-based company said in a statement.
"The safety of our customers and partners (employees) is of utmost importance."
Meanwhile, supermarkets were facing similar problems.
"All problem products have been banned from our stores," an executive at Jian-Mart, a popular supermarket chain, told AFP.
The government agency in charge of product quality supervision on Friday issued detailed findings from a comprehensive national check, showing 24 of the 295 batches it tested from the three dairy brands were contaminated.
"The manufacturers should of their own accord recall all products where melamine has been detected," the agency said on its website.
Officials at the firms could not be reached for comment.
The recall came after the government announced on Wednesday that baby milk powder from 22 dairy companies contained traces of melamine, leading to the deaths of four babies and sickening more than 6,200 others.
Symptoms have included kidney stones, an inability to pass urine and vomiting, although there have been no reports of adults suffering such problems from drinking tainted milk.
Melamine is normally used to make plastics but it can also make milk and other food products appear to have a higher protein content than they actually do.
It has become apparent in recent days that people in China have been deliberately watering down the milk to cut costs, then adding in the melamine to boost the protein content and make the product look normal.
Some Chinese press reports said the scam had been going on for years, with China's chaotic and corrupt food safety system unable either to detect or prevent it.
Starbucks customer Cathy Wang called for the government to take the toughest action possible against those responsible.
"The criminals deserve to be sentenced to death and there should be a public trial. They are more evil than murderers," said Wang, a jewellery retailer, as she sipped on a cup of tea in a Beijing Starbucks outlet.
"And the supervisory authorities, they should be punished harshly as well for neglecting their duty."
At a Beijing supermarket, Cui Hongchun, 36, expressed concern and fury over previously buying milk for his eight-year-old son from one of the suspect brands.
"I'm very worried about the milk we bought because it claimed to contain high levels of protein," he said. "I will sue them if the milk causes any problems for my boy."
The government has already announced the arrest of 18 people for their roles in allegedly providing the melamine or mixing it into milk.