China flooding: Terrifying video shows train passengers trapped in neck-high water

Parts of central China are inundated after a once in a thousand-year flood, with terrifying footage emerging of train passengers trapped in neck-high water.

At least 25 people have been killed in the central province of Henan - 12 of whom died after floodwaters submerged a subway line in its capital Zhengzhou.

More than 500 were pulled to safety after the subway tunnel flooded, while social media video and images showed train commuters immersed in deep waters in the dark and one station reduced to a large brown pool.

Officials say the three days of torrential rain have matched levels only seen once in 1000 years. They say the rainfall had caused a 20-metre breach in the Yihetan dam in the city of Luoyang west of Zhengzhou, and that the dam could collapse at any time.

More rain is forecast across Henan for the next three days, and the People's Liberation Army has sent more than 5700 soldiers and personnel to help with search and rescue.

From Saturday to Tuesday, 617.1 mm of rain fell in Zhengzhou, almost the equivalent of its annual average of 640.8 mm.

Reuters / Newshub.