Shanghai stocks plunged almost four percent Monday morning while Hong Kong also tumbled after another batch of data highlighting weakness in China's economy, while dealers are also on edge over flaring Middle East tensions.

The benchmark Shanghai Composite Index sank 3.94 percent, or 139.27 points, to 3,399.91, while the Shenzhen Composite Index, which tracks stocks on China's second exchange, slumped 5.34 percent, or 123.28 points, to 2,185.63.

Hong Kong's benchmark Hang Seng Index lost 2.31 percent, or 505.20 points, to 21,409.20. (AFP)