At least 25 people died in severe flooding Tuesday in a Chinese provincial capital while tens of thousands were forced from their homes.
Another seven people were reported missing, provincial officials said at a news conference.
Zhengzhou, the capital of Henan province, was hit by 20 centimetres of rain in one hour, the official Xinhua News Agency said, citing the Henan weather agency.
According to Chinese authorities, the rainfall in the region was the heaviest on record since weather patterns were compiled 60 years ago.
The city of Zhengzhou saw a year's worth of rainfall in three days, according to the same sources.
The torrent of rain turned streets into rapidly flowing rivers and inundated metro stations and cars.
One metro passenger wrote on Weibo that rescue workers opened the roof of his carriage to allow passengers to be evacuated one by one. Other images showed a passenger sitting on the roof of his car half-submerged in a tunnel.
Videos posted online showed entire neighbourhoods covered in waist-deep water and vehicles floating in the muddy mire.
To the north of Zhengzhou, the famed Shaolin Temple known for its Buddhist monks’ mastery of martial arts was badly hit. Henan province is home to many cultural sites and a major base for industry and agriculture.
At least 12 people had died and 200,000 people had been moved to safer places, authorities said.
Stranded people were spending the night in their workplaces or checked into hotels.
According to state television, President Xi Jinping said that "dams have collapsed, causing serious injuries, deaths and damage. The situation on the flood front is extremely serious."
Wang Guirong, a 56-year-old restaurant manager, said she planned to sleep on the couch in her restaurant after being told there was no power in her neighborhood. The State Grid Zhengzhou Power Supply Co. said a downtown substation was forced to shut down because of the rain.
“I have lived in Zhengzhou all my life and have never seen such a heavy rainstorm as today,” Wang said.
Also in Henan, near the ancient capital of Luoyang, the army said a dam was in danger of collapsing after a 20-metre breach in the structure.
The city of Luoyang, west of Zhengzhou, has a population of around 7 million.
The Yihetan dam "may break at any moment," the military warned.
China's military has blasted a dam to release the floodwaters while soldiers have also been deployed along other rivers in the region to reinforce the banks with sandbags.
China experiences regular flooding during the summer, but the growth of cities and conversion of farmland into subdivisions has raised the impact of such events.