Some plastic medical waste had been recycled to make kitchenware, he said.

The investigation is part of a nationwide review. The authorities are testing thousands of mothers and children who they fear may have been at risk of contracting HIV while being treated at hospitals in Shymkent, about 1,600km south of the capital.

Officials say 78 toddlers and eight mothers in the south have contracted HIV in recent months, and at least six children have died from HIV/Aids contracted through medical negligence.