Almost exactly five years after Hurricane Maria left Puerto Rico in the dark, the US territory is once again facing a power crisis. On Sunday, LUMA Energy, the company that operates the island’s electrical grid, announced that all of Puerto Rico had suffered a blackout due to Hurricane Fiona, reports Reuters.

With the storm nearing the island’s southwest coast, the National Hurricane Center warned of “catastrophic” flooding as Fiona began producing winds with recorded speeds of 85 miles per hour. Even before making landfall at 3:20PM local time, the storm left a third of LUMA’s customers without power. On Twitter, Puerto Rico Governor Pedro Pierluisi said the government was working to restore power, but after the events of five years ago, there’s worry there won’t be an easy fix.

In 2017, Hurricane Maria caused the largest blackout in US history when the Category 5 storm battered Puerto Rico, leaving 3.4 million people without power. The island had only recently begun rebuilding its weakened infrastructure, with blackouts a daily occurrence in some areas. Officials have tried to stress that Hurricane Fiona won’t bring a repeat of 2017. “This is not Maria, this hurricane will not be Maria,” Abner Gomez, the head of public safety and crisis management at LUMA Energy, told CNN before Sunday’s power outage. At the moment, the company is estimating it may take several days to restore power, and asked customers for "patience" while it works to respond to the natural disaster.