SEOUL, April 29 (Xinhua) -- At least 25 people were killed in a blaze that broke out at a warehouse construction site in Gyeonggi province, South Korea, local media cited fire authorities on Wednesday.

The fire started at about 1:32 p.m. local time from the basement floor of the warehouse construction site in Icheon, some 80 km southeast of the capital Seoul.

When the fire broke out, nearly 80 workers from nine companies were inside the building.

Of the total, 25 were confirmed dead, and seven others were injured. The death toll is expected to rise as many workers were still unaccounted for.

Citing the fire authorities, Yonhap news agency reported that the fire may have caused by an unexpected explosion accident during construction work using urethane, a combustible chemical used for insulation work.