Two people were executed Tuesday for their roles in the country's tainted milk powder scandal last year, which killed six children and made more than 300,000 sick.

The men were convicted of charges that included endangering public safety and producing and selling toxic food.

Parents reacted to the news by saying they were more concerned about the long-term care of those made ill by the tainted milk. They also called for further investigation into the case.

According to a statement from the Shijiazhuang Intermediate People's Court, Zhang Yujun was executed for endangering public safety and Geng Jinping was put to death for producing and selling toxic food.

Their sentences were upheld in March by an appellate court in the northern city of Shijiazhuang after the two had lodged appeals against death sentences handed down by a local court on Jan 21.

The tainted milk scandal was one of the country's most serious food safety breaches. It involved the addition of the industrial chemical melamine to infant formula. The chemical subsequently caused kidney stones and kidney failure among some children.

Melamine, which is used during the manufacture of plastics and fertilizer, was added to watered-down milk to fool inspectors who were testing for protein content. The chemical was used in an attempt to boost profits.

In total, 21 people were tried and sentenced in Shijiazhuang in January for their involvement in the scandal.

Two received death sentences, one got a suspended death sentence and the other 18 were jailed for between two years and life.

Zhang, who prosecutors named as one of the "principal criminals", was found guilty of producing 776 tons of melamine-laced "protein powder" and selling 600 tons of it to middlemen for 6.83 million yuan ($998,000).

Geng was convicted of adding 434 kg of melamine-laced powder to about 900 tons of fresh milk to increase "protein content" during quality tests.

Sanlu Group's former board chairwoman Tian Wenhua was sentenced to life in prison in January for producing and selling fake or substandard products.

Observers said the executions underscored the government's resolve in tackling recurring food safety problems.

However, parents of children sickened by the tainted milk said Tuesday they cared less about the executions than the health of their children.

Dong Shiliang, a father from Dali, Yunnan province, said: "To some extent, I think the executions show the government's eagerness to move past the scandal, but what I want is to give all people involved in the scandal the punishment they deserve."

Zhang Ge, a 37-year-old mother from Beijing, said more executives from Sanlu and other companies caught up in the scandal should face trials.

"I want further investigation into the case because we heard executives had learned about the contamination at least six months before it was exposed and they just covered it up," said Zhang.

Dong said his 2-year-old son has a stone in his right kidney while Zhang's son had a check-up last month after passing a small stone in September.

They are paying all of their children's medical expenses. When the scandal broke last September, sick children got free medical care from local governments.

Dong said he turned down a one-off offer of compensation earlier this year because the 2,000 yuan on the table was "woefully inadequate".

According to a compensation plan unveiled at the end of last year, parents of most sick children will be offered 2,000 yuan. The families will also have access to a fund covering medical costs until affected children reach 18.

Both Dong and Zhang said they have no idea how the fund is operating.

"Nobody has ever reached me to tell me about this fund. I learned about it through the media," Dong said. "But it is reported that families must prove the illness was caused by the tainted formula, which would be really hard for us."

Lawyers representing victims said they hope the door will be open for civil lawsuits so parents can seek additional compensation.

Peng Jian, a Beijing-based lawyer, is representing Zhang in her fight for compensation.

That trial was initially set for Nov 10 but it was delayed for unknown reasons. Peng said no civil lawsuits have been heard in connection to the tainted milk scandal.

In addition to the children and their families, China's dairy industry has also been suffering as a result of the tainted milk scandal, said Li Yizhong, minister of industry and information technology.

"The output of the dairy industry has, so far, reached 80 percent of the volume it was before the scandal," he told China Daily from the sidelines of a forum on product quality.