A Chinese city hit by torrential storms that killed at least three people closed its flooded subway system Tuesday, as it braces for further severe downpours.

Unverified videos on social media showed passengers in a flooded underground train carriage in central Zhengzhou clinging to handles as the water surged up to shoulder height, with some standing on seats.

Water could be seen gushing through an empty underground platform in state broadcaster CCTV's footage.

The city's subway operator said in a statement Tuesday that it would close all stations on all its lines due to the bad weather.

At least one person died and two more were missing since the heavy rain started Monday, according to the state-run People's Daily, which reported that houses have collapsed.

Local media reported earlier that two people had been killed when a wall collapsed in another district of the city.

Weather authorities issued the highest warning level for central Henan province, as CCTV showed residents of flooded streets being rescued in rafts, with one emergency worker carrying out a baby.

Footage showed one man sitting on top of his half-submerged car in an underpass.

Floods are common during China's rainy season, which causes annual chaos and washes 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 disrupt floodplains that had helped absorb the summer surge.

Earlier this month hundreds of flights were cancelled in the capital Beijing and other nearby cities with schools and tourist sites closed as torrential downpours and gale-force winds battered the region.