At least a dozen people dead as floods, heavy rainstorms hit central China

At least 12 people have died after torrential rains flooded the subway in the central Chinese city of Zhengzhou.

The city of more than 10 million people in Henan province "has experienced a series of rare and heavy rainstorms, causing water to accumulate in Zhengzhou metro", city officials said on Wednesday in a Weibo post, adding 12 people died and five were injured on Wednesday.

Authorities have issued the highest warning level for Henan province as record floods hammer the province.

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Seasonal floods are common in China, but scientists say climate change is bringing increasingly extreme weather patterns.

Shocking images

Images poured across Chinese social media showing dramatic rescues of pedestrians in Zhengzhou from torrents gushing through the streets.

The Chinese army warned that a stricken dam in the centre of the country "could collapse at any time" after being severely damaged in torrential storms that killed at least three people and brought the region to a standstill.

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Annual floods during China's rainy season cause chaos and wash away roads, crops and houses.

But the threat has worsened over the decades, due in part to widespread construction of dams and levees that have cut connections between the river and adjacent lakes and disrupted floodplains that had helped absorb the summer surge.

According to the authorities, the rainfall was the heaviest since record-keeping began 60 years ago, with the city seeing the equivalent of a year's average rainfall in just three days.