BEIJING, CHINA (AFP) - Two men were executed in China on Tuesday for their roles in a scandal over contaminated milk powder that led to the deaths of at least six infants and sickened up to 300,000, state media said.

The men had been sentenced to death earlier this year by a court in the northern city of Shijiazhuang for producing and selling toxic ingredients that ended up in the infant milk powder, Xinhua news agency said.

Zhang Yujun and Geng Jinping were put to death following execution orders issued by China?s high court and after their appeals were turned down in March, Xinhua said.

It cited a statement from the Shijiazhuang Municipal Intermediate Court in Hebei province. AFP calls to the courts went unanswered.

The Xinhua report did not say where the men were executed.

The scandal came to light in September 2008, reviving fears over product safety in China and leading to recalls and bans around the world of goods containing Chinese dairy products.

According to Xinhua, Zhang was convicted of producing and selling more than 770 tonnes of protein powder laced with the industrial chemical melamine from July 2007 to August 2008.

The chemical was mixed into milk to give the appearance of higher protein content.

Geng was found guilty of selling milk tainted by the powder to dairy brokers as well as to the now-defunct Sanlu Group, a dairy company that was at the centre of the scandal, it added.

The scandal erupted just after the Beijing Olympics in August 2008, and there were widespread reports that the government had sought to cover it up to prevent embarrassment during the Games.

At least six babies died and nearly 300,000 others fell ill with kidney stones and other urinary tract problems after being fed dairy products laced with the melamine.

Altogether 21 people have been convicted for their roles in the scandal including former Sanlu boss Tian Wenhua, who was given life in prison.

One other person was given a suspended death penalty, a sentence that routinely gets commuted to life in jail, while 15 others were imprisoned for terms ranging from two to 15 years.