South Korean authorities started cleanup operations on Thursday after powerful typhoon Chaba left six people dead and four missing. The storm lashed South Korea's southern coast with powerful winds and heavy rains that triggered flash floods in the area.

Chaba is the eighteenth typhoon to hit the Pacific this year. Last month Typhoon Lionrock and Typhoon Malakas killed 23 people after making landfall in the region.

In the industrial city of Ulsan, a man drowned near his apartment and a woman was found dead at a flooded underground parking lot.

Video from public surveillance cameras showed cars, refrigerators and other debris floating down flooded streets and people struggling through muddy, chest-deep water.

Other footage posted on social media showed waves shattering the glass windows of seafront stores and a wooden house having its roof sheared off after slipping into a swollen river and being carried under a low bridge.

More than 230,000 homes across the coastal area suffered power outages, but the Korea Electric Power Corporation said supplies had been restored by Thursday morning.

Hyundai Motors had to suspend production at two car plants due to flooding.

Travel chaos also ensued as more than 100 flights were cancelled and high-speed rail services were suspended.

In the country's second largest city of Busan, a labourer was killed when strong winds toppled a heavy crane.

The storm also disrupted preparations for Asia's largest movie showcase, the Busan International Film Festival, which was scheduled to open Thursday evening.

Festival events planned on Busan's main beach had to be cancelled or moved indoors after the strong winds blew away or damaged the temporary venues erected on the sand.

The typhoon had triggered severe storm warnings in Japan, but was downgraded to a tropical cyclone over the Sea of Japan (East Sea) before it hit Japan's Honshu island on Wednesday evening.