People gather in a plaza as Cuba is hit by an island-wide blackout, in Havana, Cuba, October 18. (Photo credit: Norlys Perez/Reuters/File via CNN Newsource)

Havana, Cuba (CNN) — Cuba’s energy grid has collapsed, leaving millions without power, the latest in a series of failures on an island struggling from creaking infrastructure, natural disasters and economic turmoil.

The state-run utility company, the Cuban Electric Union, said workers were attempting to get the grid back online but local officials warned residents the difficult process of restoring power to aging Soviet-era power stations could take days.

Cuba’s top energy producer, the Antonio Guiteras power plant in Matanzas, suffered an overnight failure, prompting the grid’s collapse on Wednesday, the company said.

Residents woke up in darkness early Wednesday morning. In Havana, the streets were nearly pitch black as the sun rose over the capital city. The only visible lights came from a handful of government facilities, large hotels and vehicle headlights.

The government has ordered the “suspension of work and teaching activities,” Cuba’s Minister of Labor and Social Security, Marta Elena Feito said.

“This measure will remain in place for the duration of the crisis. Vital services will continue to function and there will be no salary impact,” state media quoted her as saying.

Cuban officials say US economic sanctions, which increased under the previous Trump administration, have further crippled the already ailing energy sector, although critics also fault a lack of government investment in infrastructure.

For nearly a week in October, most of Cuba suffered near-total blackouts, the worst energy outages in decades.

Cuba’s energy and mines ministry said “conditions are more favorable now than in the last disconnection” and that the system was gradually being restored. It also said it has already created “generation islands” microgrids, the initial step in getting the power back on.

Even so, Cubans will still have to deal with daily scheduled blackouts that the government set up as an energy-saving measure. Some of those planned outages can last more than 12 hours a day in communities outside Havana.

Cuba suffered from several power grid failures in October, which were initially caused by a lack of fuel at power plants that officials struggled to get back online because they were so outdated. The country’s national power grid collapsed again when Hurricane Oscar hit in late October, killing at least seven people.

Another storm, Rafael, slammed into western Cuba in early November as a Category 3 hurricane, yet again knocking out power across the island and flooding parts of its western provinces. Days later, a 6.8 magnitude earthquake struck off the coast of eastern Cuba just an hour after a 5.9 magnitude quake also impacted the region. Homes and power lines were damaged and landslides were reported in several communities.

This is story has been updated.

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