Tuesday its steelmaking plant at Muroran Works in northern Hokkaido has been suspended since Sunday due to a fire, but it plans to restart operations by Oct. 10.

The company is investigating the cause of the fire, a Nippon Steel spokesman said.

The shutdown follows two recent suspensions of steelmaking plants in the group.

Last week, Nippon Steel said one of the two steelmaking plants at its Kimitsu Steel Works would be shut until the end of December for repairs to a chimney that collapsed in a typhoon last month.

Another steelmaking plant at a Nippon Steel subsidiary in western Hiroshima, Kure Works, has also suspended operations since a fire damaged its operating room in late August.

The spokesman reiterated on Tuesday that the company still does not know when the Kure plant will resume operation, but the world's No.3 steelmaker plans substitute production from other plants and will ask other Japanese steelmakers to provide substitute material to reduce disruption to supply for customers, including automakers.

(Reporting by Yuka Obayashi; editing by Jason Neely)