Hong Kong stocks tumbled on Wednesday as Asian markets retreated on recession fears and as traders re-evaluated their recent big bets on China's reopening, even as mainland officials unveiled fresh measures to roll back Covid restrictions.

The Hang Seng Index dived 3.2 percent, or 626 points, to 18,814.

The Shanghai Composite Index fell 0.4 percent, or 12 points, to 3,199, though the Shenzhen Composite Index edged up 0.2 percent, or 3 points, to 2,071. (AFP)