At least eight people have died and 14 others have been injured as flooding caused by torrential rain hit parts of South Korea's capital Seoul.

Heavy downpours on Monday night submerged roads, flooded metro stations and caused blackouts across the city and neighbouring provinces.

Some areas received the highest rate of rainfall in 80 years, Korea's meteorological agency said.

Weather officials said the rain was likely to continue over several days.

Images showed floodwater gushing down the steps of metro staircases, parked cars submerged up to their windows and people making their way across streets in knee-high water.

Local reports said three victims - two sisters in their forties and a 13-year-old girl - were living in a semi-basement apartment known as a banjiha.

These apartments, located below street level, gained prominence after being featured in the Oscar-winning South Korean film Parasite, which told the story of a poor family in such an apartment trying to find ways to make ends meet.

Rescue officials said they were unable to access the apartment as floodwaters had risen to waist-high levels on the street.

Parts of Seoul, the western port city of Incheon and Gyeonggi province surrounding Seoul charted rainfall of over 10cm per hour on Monday night, according to Yonhap news agency.

Meanwhile, Seoul's Dongjak district recorded more than 141.5 mm of rain per hour - the highest rate since 1942, according to Korea's Meteorological Administration (KMA).

The other victims included a person who was electrocuted, one person was found under the wreckage of a bus stop and another died in a landslide. At least 14 were injured and six others reported missing.

At least 163 people in Seoul have been made homeless and have taken shelter in schools and public facilities, according to Yonhap.

The downpour also affected public transportation, as flooded railroads forced suspension of railway services in Seoul and Incheon.

South Korean president Yoon Suk-yeol ordered government officials to evacuate residents from high-risk areas, and urged businesses to grant employees flexible commuting hours on Tuesday morning.

The KMA continued to issue heavy rain warnings across Seoul and surrounding metropolitan areas, and said it expected rainfall for the central part of the country to continue at least until Wednesday.