The Aji Chiban snacks chain has been told by China's Consumer Council to warn parents that they may need to keep a close eye on their children, in case exposure to "stone chocolate" sweet products sold by the chain lead kids to try and eat real stones. The confectionery, which is sold in China, Singapore, the Philippines and Britain, has been on the market for a year and no serious incidents have been reported, but Aji Chiban spokesman Kenny Yeung said that the store will carry out an investigation and consider issuing a warning.