HONG KONG — China's mainland stock markets opened lower Wednesday morning after a historic one-day decline in Hong Kong, as investors digested recent moves by Chinese authorities to support the economy and doubts grew for more.
Major mainland indices reversed the trend to open higher. The CSI 300, which measures large market caps listed in Shenzhen and Shanghai, fell 4% in Wednesday's morning session, while the tech-oriented STAR 50 fell more than 9% and the ChiNext fell more than 7%.