Cuba’s power grid collapsed Friday night, triggering a nationwide power outage and plunging its more than 10 million people into darkness.

The grid failed on Friday evening about 8:15pm (00:15 GMT) after a breakdown at Diezmero substation in the capital, Havana, kicked off a chain reaction that shut down power generation across the island, according to officials at operator Union Electrica (UNE).

Pockets of Cuba's capital Havana saw the lights flicker back on though vast areas of the city and country continued without electricity on Sunday morning, after a nationwide grid collapse that knocked out power to 10 million people.