Activist Zhao Lianhai was released by police early yesterday morning after 12 hours during which he was questioned and threatened with jail if he continued to speak out for infants made ill by melamine-tainted milk powder. 'I told them, I couldn't stop. I will persist, even if it means I'll be broken into pieces,' Zhao wrote on Twitter yesterday. 'This is because what's at stake right now is the welfare of the children.' Zhao said police did not give him food during questioning in Beijing. He was only allowed home at 1.30am. The organiser of the Jieshibaobao (kidney stone kids) group, set up after the 2008 scandal, Zhao was convicted of 'provoking quarrels and making trouble' in November and sentenced to 21/2 years in jail. He was released on medical parole in January. Zhao was taken away by three men on Thursday after trying to protest outside the China Dairy Industry Association, which manages a compensation fund set up by the milk companies. Earlier this month Xinhua-affiliated magazine Oriental Outlook reported that the operation of the 1.1 billion yuan (HK$1.32 trillion) fund was highly opaque. Melamine-laced milk formula caused kidney stones in thousands of mainland infants, killing six. An industrial chemical, it was added to substandard milk to boost its nitrogen content, allowing it to pass testing for protein levels. 'According to officials, about 5 per cent of parents didn't sign the compensation agreement,' Zhao said yesterday. 'Even that would mean 15,000 children not being looked after. But we know in reality that more parents have not signed the unfair agreement.' The agreement requires parents to give up the right to sue in return for just 2,000 yuan and medical expenses until the child reaches 18, in the majority of the 300,000 cases.