Heavy rains battered northern China on Monday, killing at least two people in Beijing while washing away cars and forcing the capital to issue its highest alerts for flooding and landslides.

Storm Doksuri, a former super typhoon, has swept northwards over China since Friday, when it hit southern Fujian province after scything through the Philippines.

Emergency personnel recovered two bodies from waterways in Beijing's Mentougou district on Monday, the state-run People's Daily said.

AFP reporters saw tree branches and dented cars, left by receding floodwaters, strewn on riverbanks in Mentougou on Monday afternoon.

"This morning it was crazy, the water overflowed the Mentougou river and the whole avenue was flooded," Guo Zhenyu, a 49-year-old resident, told AFP.

Yellow bulldozers, workers in orange mackintoshes and residents cleared away the mud and debris during a period of lighter rain on Monday afternoon.

"I'm old but I've never seen flooding like this before in my life," Mentougou resident Qin Quan said.

She showed AFP a video on her phone, shared among residents of the area, of workers attempting to resuscitate an unconscious man, as well as footage of a man desperately clinging to a pole with one hand as water washes over him.

The much larger and still swollen Yongding River in the same district churned up debris in brown torrents as residents looked on in shock from a bridge.

Chen Hong, a resident of the southern Fengtai district, shared footage with AFP that showed a parked van half-submerged in fast-flowing brown water on Monday morning as the rain continued to fall.

Residents in Chen's neighbourhood cleared mud outside their homes with shovels during a brief respite from the downpour.

"Once it starts raining the road turns into a drain, and there's water on the first floor inside houses," said Chen, 52.

"The houses here are all old houses, so there are definitely concerns about safety," she said.

A section of road surface in the outer Fangshan district caved in under rising water, local media reported.

Hundreds of bus services in the capital were suspended, according to state news agency Xinhua, while the city government issued the highest flood warning for the suburban Dashihe River.

Social media users uploaded footage of vehicles swept away by muddy torrents and thoroughfares turned into rapids on the outskirts of the city.

Murky water can be seen in one clip posted on the Instagram-like Xiaohongshu platform on Monday swamping a large intersection in the outer Mentougou district next to high-rise apartment blocks. The clip was geolocated by AFP.

Rainwater also appeared to leak onto a subway platform in western Beijing's university district in another Xiaohongshu video from Sunday that was geolocated by AFP.

- Extreme weather -

The streets of central Beijing were quieter than usual on Monday morning as residents heeded official recommendations to work from home, with only a handful of delivery drivers braving pools of water seen in usually packed bike lanes.

The governments of Beijing and neighbouring Hebei province renewed red alerts for rainstorms on Monday.

China has been experiencing extreme weather and posting record temperatures this summer, events that scientists say are being exacerbated by climate change.

Experts have warned that the ongoing downpour could prompt even worse flooding than in July 2012, when 79 people were killed and tens of thousands evacuated, according to local media.

An average of 170.9 millimetres of rain inundated Beijing in 40 hours between Saturday night and noon on Monday, the Beijing Meteorological Bureau said.

That is almost equivalent to the average rainfall for the entire month of July, according to official records.