Cuba reconnected its national electrical grid and restored power to the majority of the capital Havana by late on Sunday, energy officials said, nearly two days after an island-wide outage knocked out power to 10 million people.

Cuba suffered a massive power outage Friday night affecting Havana and the country's provinces that left millions in the dark.

Cuba has struggled with blackouts in recent months, including a nationwide one in December. Friday’s power failure was the fourth widespread one in five months. Government officials blame U.S. economic sanctions for the ongoing crisis, while others point to aging infrastructure, fuel shortages and the island’s susceptibility to hurricanes.