Hong Kong stocks sank on Friday as optimism over a US debt deal was overshadowed by a tech sell-off, fuelled by disappointing earnings from e-commerce titan Alibaba that added to worries over China's economy.

The Hang Seng Index shed 1.4 percent, or 276 points, to 19,450.

The Shanghai Composite Index lost 0.4 percent, or 13 points, to 3,283, while the Shenzhen Composite Index added 0.1 percent, or 2 points, to 2,031. (AFP)