Xinjiang authorities yesterday revealed that a boy who died at hospital last month had kidney problems and his parents had given him Sanlu milk formula.
Doctors, however, could not confirm that is what killed him.
The announcement came as officials in Hebei said 12 more people had been arrested in the widening investigation into the mainland's tainted milk powder crisis.
The eight-month-old boy died five hours after arriving at a hospital in Yanqi township, about 250km south of the capital Urumqi on August 7, said the facility's party secretary, Zhou Xiyuan .
Mr Zhou said the cause of death was mainly respiratory failure, although the hospital admitted there was problem with the infant's kidney and that his parents had fed him Sanlu milk powder.
'There is not sufficient evidence to suggest the boy died because of Sanlu,' Mr Zhou said.
