A powerful typhoon killed at least one person in South Korea on Sunday, grounded 280 flights and stranded 15,000 passengers on its southern resort island of Jeju, officials said.

The anti-disaster agency reported one dead and two missing on Jeju. South Korea's Yonhap news agency put the total typhoon death toll at six — on Jeju and elsewhere.

The agency said Typhoon Nari, expected to hit the mainland late Sunday, moved faster than the country's weather office had expected, flooding scores of houses and leaving more than 100 people homeless.

The powerful storm also cut power to some 150,000 homes on Jeju and parts of southwestern South Jolla province for hours.

The weather office said the storm had brought more than 200 millimetres (eight inches) of rain to Jeju.

"All flights coming in and out of Jeju — 240 domestic flights and 40 international flights — have been cancelled," Han Kum-Hyun, an official at Jeju airport, told AFP. "Some 15,000 air passengers have been stranded."

More than 3,000 vessels remained harboured at ports around the island as local maritime authorities banned all ferries and fishing boats from operating.

Weathermen forecast up to 300 millimetres of rain in the southwest until Monday, warning residents against possible flood damage.