Tainted milk killed six babies and made hundreds of thousands of others ill
A year on from China's tainted milk scandal, there are allegations that the practice of selling milk contaminated with the chemical melamine continues.
Prosecutors in Shanghai have confirmed to the BBC that three dairy executives are to go on trial for allegedly selling milk tainted with melamine.
Reports suggest the authorities knew about the contamination but failed to inform the public.
Six children died and 300,000 became ill from tainted milk in 2008.
Melamine is an industrial chemical used in the making of plastics and fertilisers. If ingested it can cause kidney failure and kidney stones.
Some Chinese dairy producers were convicted of watering down their milk to make supplies go further, then adding melamine so that it appeared to have a higher protein content.
10 Sept 2008: Fourteen babies reported ill in Gansu province
15 Sept: Beijing confirms first deaths from the contamination
22 Sept: Number of ill babies soars to tens of thousands
23 Sept: Other countries start to recall Chinese dairy products
31 Oct: Melamine routinely added to animal feed, say China media
23 Dec: Main dairy firm involved, Sanlu, goes bankrupt
31 Dec: Four senior Sanlu executives go on trial
2 Jan 2009: Firms say sorry in mass New Year text message
22 Jan: Two men sentenced to death and 19 jailed in Hebei
March: Higher courts reject appeals
24 Nov: Zhang Yujun and Geng Jinping executed
In late 2008, the government ordered 22 firms implicated in the scandal to pay millions of dollars in compensation to the families affected by the contaminated milk.
The firms' milk products were supposed to have been destroyed.
Two people were executed in November last year for their part in the scheme and 19 other people have been jailed.
Now, prosecutors in Shanghai have told the BBC that three executives from Shanghai Panda Dairy Company are to go on trial within a week.
The company was shut down and the executives arrested for allegedly selling dairy products a year ago that contained melamine.
The BBC's Chris Hogg in Shanghai says it impossible to confirm details of the allegations because the company has been shut down, and Shanghai government departments connected with the case refer all enquiries to each other.
The state-run China Daily reported that local authorities discovered the contamination at the end of 2008 and launched an investigation in February 2009, but did not tell the public or recall Panda dairy products.
Some commentators in China have suggested that this was because officials were worried another scandal would harm the dairy industry as it tried to recover from the first one, says our correspondent.
China was supposed to have imposed tougher regulations on the dairy industry to protect consumers after children first started falling ill from tainted milk in September 2008.
Government officials have said the Shanghai case is unconnected with the 2008 poisonings and did not involve tainted products that should have been destroyed in the scandal's aftermath.