The BBC's Peter Biles: "Nature at its most merciless"

Mr Zhu said local leaders must protect lives and property, reinforce flood defences and organise effective rescue teams.

More than 1,000 people have died in China this year in flooding caused by unusually heavy and early summer rains, according to official figures published last week.

More flood warnings

Mr Zhu's orders coincided with a warning from disaster relief officials that a huge surge of flood water was heading towards the middle reaches of the Yangtse.

Thousands of sandbags are being used to protect riverbanks

The flooding has weakened and breached protective embankments all along China's longest river.

One of the worst-hit areas is the industrial central city of Wuhan. Torrential rains have flooded streets to waist level in some areas.

Around 7,000 soldiers and civilians have been mobilised to help control the mass of floodwater by reinforcing defences.

Health officers help keep disease at bay

Health teams have been spraying disinfectant in cities to help stop the spread of disease.

It is feared that the flooding could continue for weeks to come.

About 140 million people have been affected so far. China's Civil Affairs ministry has estimated the damage at more than $10bn.