SHIJIAZHUANG, China (AP) -- More than a 1,000 parents anxious over tainted milk powder on Thursday rushed their infants to hospitals for health checks as the government announced that a fourth baby had died in the spreading scandal.
Meanwhile, regulators in Hong Kong ordered the recall of milk products from a Chinese dairy after finding the banned industrial chemical melamine in eight of 30 sample products tested.
Police in Hebei province said they had arrested 12 more people Thursday, bringing the total to 18. Shi Guizhong, spokesman for the provincial police, said six allegedly sold melamine, while the other 12 were milk suppliers accused of adding the chemical to milk.
The official Xinhua News Agency said the latest death was a baby in the far western region of Xinjiang. However, an official at the No. 2 Agriculture and Production Corps. Hospital in Yanqi, Xinjiang, said it was too early to say if the 8-month-old baby died of complications caused by the tainted milk powder.
Shi said Hebei police and government officials were starting a 10-day campaign to focus on melamine contamination. Suppliers to the dairy companies are believed to have added the banned chemical, normally used in plastics, to watered-down milk to make it appear higher in protein.
Police also confiscated 660 pounds of suspected chemicals, including 490 pounds of melamine, he said. An additional 87 people were summoned for questioning and 28 people have been detained, according to Shijiazhuang Vice Mayor Zhang Meizhi.
One suspect, surnamed Su, told police that from February 2007 to July 2008 he bought 200 44-pound sacks of melamine $29 each, and sold them all to milk suppliers, Shi told a news conference.
At the Beijing Children's Hospital Thursday, more than 1,000 anxious parents waited for check ups as they carried their sleeping infants and toddlers. By 2 p.m, doctors had seen only half of the 1,200 who waited in line.
Nervous parents said their children had all been drinking three major brands of baby milk powder, all of which have been recalled after government tests found melamine.
Fang Sunyi, 28, who was holding her 3-month-old son, said he had been fed Sanlu Group Co. and Guangdong-based Yashili since birth.
"I'm just praying there's nothing wrong with my son," she said. "We first fed him Sanlu, then stopped because that was reported to be bad quality, then we switched to Yashili, but now there's nothing left. We don't know what's safe anymore and we don't want to take any chances."
In Shijiazhuang, Hebei's capital, the new chairman and chief executive officer of Sanlu, the dairy company whose milk powder has been linked to all of the known illnesses, apologized at a news conference Thursday.
Zhang Zhenling said he wanted to "express deepest apologies" for the tainted milk powder and for "harm and losses to consumers." He then bowed three times.
Zhang pledged that Sanlu would "turn pressure in motivation" to resolve the crisis properly. His predecessor was fired earlier this week and has been detained by police.
Parents gathered outside Sanlu's headquarters in Shijiazhuang to get refunds for their purchases of tainted milk powder. The mood was calm but there was confusion as parents traded tips on what products they thought were safe.
A 30-year-old mother who gave only her surname Wang said her 1-year-old daughter seemed healthy but that she was still worried. The three major milk powder brands that she usually buys -- Yili Industrial Group Co., Mengniu Dairy Co. and Sanlu -- have all been recalled.
"Of course as a mother, I was really nervous," she said. "Now we have no idea what kind of milk to give the baby. They all have problems."
The widening crisis has raised questions about the effectiveness of tighter controls China promised after a series of food safety scares in recent years over contaminated seafood, toothpaste and ingredients for pet food.
The Hong Kong recall covers milk, yogurt, ice cream and all other products made by Yili Industrial Group Co. and distributed in Hong Kong, said Constance Chan, controller for the territory's Food Safety Center.
In addition to the recall in Hong Kong, Singapore authorities announced they were recalling an ice cream bar made by Shanghai Yili AB Foods after melamine was found in it.
China's government has dispatched thousands of inspectors to monitor milk powder producers after health officials reported Wednesday that the number of babies sickened by tainted formula rose to 6,244.
This is the second major case in recent years involving baby formula. In 2004, more than 200 Chinese infants suffered malnutrition and at least 12 died after being fed phony formula that contained no nutrients.