Seoul - Six people were killed in a fire early Friday in a 10-storey boardinghouse in the city of Yongin, 40 kilometres south of Seoul, local media reported.

Four people were injured in the fire, and some are in critical condition, according to Yonhap news agency.

The fire broke out at 1:20 am on the ninth floor of the residential building as guests were sleeping. Inhalation of toxic gas was believed to have caused the deaths, reported Yonhap from police sources.

Police suspect arson as there were signs that the fire started in two different rooms. It took firefighters 40 minutes to extinguish the blaze. (dpa)