Energy ministry officials said an electrical substation in Havana failed around 8.15pm, knocking out power to a large swath of western Cuba, including the capital.

The lights were out across all of Havana’s waterfront skyline, a Reuters witness observed, with only a scattered few tourist hotels operating on fuel-fired generators.

Reports on social media from outlying provinces both east and west of the capital city suggested much of the country of 10 million people was without power.

The grid failure follows a string of nationwide blackouts late last year that plunged Cuba’s frail and antiquated power generation system into near-total disarray, stressed by fuel shortages, natural disaster and economic crisis.

Hours-long rolling blackouts have been the norm for months. Severe shortages of food, medicine and water have made life increasingly unbearable for many Cubans, who in recent years have fled the island in record-breaking numbers.