A vast area of earthquake-hit Chile, including the capital city of Santiago, has been plunged into darkness by a massive blackout, the National Emergency Office said.

Officials say the area without power covered a 2,000-kilometre stretch affecting about 80 per cent of Chile's population of 17 million people.

Power went out in the capital just before 9:00pm (local time) on Sunday, and there were also reported problems with phone services.

It is not known if the blackout is related to the massive 8.8-magnitude quake that rocked central Chile on February 27, or to the numerous aftershocks that have shaken the country since.

Officials says a power grid failure triggered a loss of electrical service from Atacama in the desert north, to the temperate central region where Santiago sits, to the much cooler south all the way to Chiloe island.

- AFP