(Corrects volume milestone in headline and first paragraph to July, not 2-1/2 months)
SHANGHAI, Nov 5 (Reuters) - China's stocks extended the gains on Thursday as investors jumped into blue-chip shares, driving trading volume to its highest since late July.
The CSI300 index of the largest listed companies in Shanghai and Shenzhen rose 2.1 percent, to 3,705.97, while the Shanghai Composite Index gained 1.9 percent, to 3,522.82 points.
The market was boosted by optimism over the Hong Kong-Shenzhen stock market connect scheme, China's plan to deepen reform on telecommunication industry, sustainable growth in Chinese economy and an upcoming meeting between the leaders of China and Taiwan.
Securities firms Industrial Securities, Huatai Security and Founder Securities all hit a daily upward limit of 10 percent.
Total volume of A shares traded in Shanghai was 55.2 billion shares, while Shenzhen volume was 42.8 billion shares. (Reporting by Ruby Lian and Pete Sweeney; Editing by Simon Cameron-Moore)