At Least 1 Dead in Puerto Rico After Hurricane Fiona Creates 'Catastrophic' Floods and Power Outages

Stephanie Rojas/AP/Shutterstock Road closed after mudslide caused by Hurricane Fiona in Cayey, Puerto Rico

At least one person was killed as Hurricane Fiona swept across Puerto Rico on Sunday.

The National Hurricane Center warned that "catastrophic and life-threatening flooding continues" there as the slow-moving Category 1 hurricane moved over the Dominican Republic on Monday.

Hurricane warnings also remain in effect for Turks and Caicos.

Puerto Rican Gov. Pedro Pierluisi estimated "billions" in damages and alerted residents that rain over the island is expected to continue through Tuesday evening, The Washington Post reported.

Pierluisi said at a news conference Monday that more than 1,000 stranded residents in 25 municipalities had been rescued, and he urged others to remain indoors, The New York Times reported.

"We are going through a difficult moment but our people are strong and very generous," he said, according to ABC News.

RELATED: Hurricane Fiona: How You Can Help People in Puerto Rico Affected by the Storm

Stephanie Rojas/AP/Shutterstock Three people inside a house awaited rescue from the floods caused by Hurricane Fiona in Cayey, Puerto Rico

The person who died was a resident of Arecibo and attempting to fill his generator with gasoline while the generator was running, resulting in an ignition, officials said, ABC News reported.

Two other deaths of people in shelters were attributed to natural causes rather than the storm.

RELATED: Hurricane Fiona Causes Entire Island of Puerto Rico to Lose Power

Monday dawned with more than 1.3 million Puerto Rican customers without electricity, according to PowerOutage.us.

Jose Jimenez/Getty Downed power lines in Cayey, Puerto Rico, which awoke to a general power outage Monday from Hurricane Fiona

LUMA Energy, the island's power company, said it could take several days before full power was restored.

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Monday saw the reopening of most airports, but Pierluisi said during his news conference that more than 2,000 people remained housed in 128 shelters across the island.

President Joe Biden approved an emergency declaration on Sunday, directing federal agencies to coordinate disaster relief.

JOSE RODRIGUEZ/AFP via Getty Flooding during Hurricane Fiona in Villa Blanca, Puerto Rico, on Sunday.

Fiona's landfall came two days before the fifth anniversary of Category 4 Hurricane Maria's assault on the island, which resulted in nearly 3,000 deaths and about $90 billion in damages.

Models show Fiona could develop into a Category 3 storm by Wednesday as it moves into the mid-Atlantic, according to the Orlando Sentinel.