BEIJING — The mother from Hangzhou doesn't let her daughter have any dairy now and worries that her baby's cries signal pain from kidney stones.

Like thousands of parents in China, Yu Lufang has a child who got sick from drinking formula tainted with an industrial chemical. Most youngsters recovered, but the anger remains.

Hundreds of affected parents, including Yu, have banded together to reject a government compensation plan they say was drawn up without their input and doesn't cover enough victims.

The government and Chinese dairy companies had hoped the nationwide scheme would ease tensions over the scandal. Instead, it has given embittered and geographically scattered parents a common cause.

The Health Ministry says 296,000 babies were sickened with kidney stones and other problems after consuming milk powder tainted with melamine, a chemical usually used to make plastics and fertilizers. When ingested in large amounts, it can cause kidney stones and kidney failure.

Six deaths have been linked to the contamination.

Zhao Lianhai, whose 3-year-old son was sickened by melamine and who was an organizer of the campaign, said Tuesday his group has gathered signatures from more than 200 parents nationwide on a letter demanding changes to the government payout scheme.

The government's plan calls for families whose children died to receive 200,000 yuan ($29,000), while others would receive 30,000 yuan ($4,380) for serious cases of kidney stones and 2,000 yuan ($290) for less severe cases.

The letter says compensation should be based on appraisals of individual cases and not just on broad categories.

Other demands include free medical treatment for babies still recovering, and the lifting of an age limit of 3 for children eligible for free treatment.

Zhao, whose son has recovered, said the group will continue to gather signatures until Thursday and then submit its letter to the Health Ministry and China's Dairy Industry Association.

Parents from provinces in the far south and in the northeast, as well as from cities like Beijing and Shanghai already have signed.

"As consumers, we suffered great injury, and the expenses and all the losses incurred in the process of getting treatment for our sick children should be paid for by the manufacturing companies," it reads.

The letter is the latest confrontation between affected families and the government over the tainted formula.

Many parents feel the government breached their trust in certifying milk powder as safe that later led to illnesses or deaths.

Among them is Yu Lufang of Hangzhou, who for almost three months before the scandal broke in September did not know why her daughter cried every time she urinated.