Residents on the Russian island of Sakhalin face restored electricity supplies on Saturday, three days after an outage plunged most of the island into darkness.

A power transmission line failed in the early hours on Wednesday, leaving 12 districts without electricity, including the towns of Kholmsk, Poronaysk and Nevelsk, formerly known as Maoka, Shi-suka and Honto, respectively.

"About 190,000 homes were affected," a spokeswoman for regional power utility Sakhalinenergo told The Japan Times on Friday.

The utility restored power on Thursday but problems persisted and outages continued in some areas.

The spokeswoman said six regions across the island will be taken offline overnight Friday to finalize repairs.

Sakhalin was the subject of a tug of war between Japan and Russia in the late 19th and early 20th centuries.

The southern half was Japanese territory from 1905 until 1945, when it was known as Karafuto Prefecture. It industries such as fishing.