Puerto Rico hit by islandwide blackout

In what’s been called the second-largest blackout in history, Puerto Rico lost power entirely on Wednesday — marking the second time the island has suffered a major power failure in less than a week.

Puerto Rico’s power authority blamed the outage on the failure of a line that originates from the U.S. territory’s largest power plant. The cause of the failure is not yet known, however.

Officials said it could take between 24 to 36 hours for power to be restored.

The outages reflect the continued fragility of Puerto Rico’s electrical grid, despite a multi-billion dollar recovery effort underway since Hurricane Maria devastated the island seven months ago.

The island’s power authority had said earlier Wednesday that electricity had been restored to 97 percent of its nearly 1.5 million customers, The New York Times reported. But just three hours later, the islandwide outage struck.

The blackout comes less than a week after a fallen tree knocked out power for about 870,000 customers.

Puerto Ricans expressed their exasperation on Wednesday at the continued grid troubles.

“This is too much,” Luis Oscar Rivera, whose power was only fully restored less than two months ago, told The Associated Press. “It’s like the first day of Maria all over again.”

San Juan Mayor Carmen Yulín Cruz, who has been critical of post-Maria recovery efforts, expressed her disdain on Twitter.

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This is a developing story. Please check back for updates.

This article originally appeared on HuffPost.