Death toll rises to 4 as Hurricane Fiona hits Puerto Rico, the Dominican Republic, and Guadeloupe

• Hurricane Fiona made landfall in Puerto Rico's southwest coast on Sunday afternoon.
• Videos from social media show flooding in parts of the island triggered by the fierce storm.

Four people have been killed due to the catastrophic flooding and high-speed winds from Hurricane Fiona.

Hurricane Fiona struck Puerto Rico on Sunday, triggering an island-wide blackout and major flooding. The storm's landfall coincides with the 5-year mark of 2017's devastating Hurricane Maria — from which the territory has yet to fully recover.

According to the National Hurricane Center, the Category 1 storm made landfall on Puerto Rico's southwestern coast, around 3:20 p.m. ET local time on Sunday, with maximum sustained winds of 85 miles per hour.

"The damages that we are seeing are catastrophic," Puerto Rico Governor Pedro Pierluisi said on Sunday, per The Associated Press.

On Monday, Pierluisi told CNN at least two people have died. The news outlet reported a 58-year-old man was washed away by La Plata River behind his home in Comerío. In a separate incident, firefighters in the city of Arecibo said one man died from burn wounds after attempting to fill his generator with gasoline.

The National Guard officials said about a 1,000 people had been rescued by emergency crews by noon on Monday, according to CNN.

As the hurricane barreled into the island, brown water rushed through streets and into homes. More than a foot of rainfall has drenched the island in several locations, and one reporting station reported more than 2 feet of rain in the last 24 hours. Nearly the entire island remains under flood warnings.

Jose Luis German Mejia, an emergency management official, told CNN, more than one million people in the country are without running water after the storm knocked 59 aqueducts out of service. One person died after being hit by a falling tree, The Washington Post reported.

The impact from the storm also killed a man in Guadeloupe. Authorities in the French Caribbean region said the man's home had been swept away and he was found dead.

On Sunday morning, U.S. President Joe Biden declared a state of emergency in Puerto Rico as the storm approached, ordering federal assistance to supplement disaster response efforts.

A video from a flooded area in Arecibo show a door-to-door search and rescue operation, with many people refusing to leave their home.

The storm downed electricity transmission lines, leading to "a blackout on all the island," according to a press release by LUMA Energy— the private company that operates power transmission and distribution in Puerto Rico. The company said it could take days to fully restore service.

On Monday morning, the head of Puerto Rico's Aqueducts and Sewers Authority said 750,000 clients don't have water on the island following the hurricane.

Fiona barraged an island that was already fragile after Hurricane Maria, a Category 5 storm which damaged houses, destroyed the power grid, and caused nearly 3,000 deaths. More than 3,000 homes still have only a blue tarp as a roof.

Another video captures the moment wind gusts from hurricane Fiona rip off the roof of a house in Ponce, on the south part of the island. It's unknown whether someone was in the house at the time.

Human-caused climate change is making hurricanes like Fiona more dangerous, according to a growing body of research. Earth's warmer and moister atmosphere and warmer oceans provide fuel for hurricanes, causing more intense rainfall and windspeeds.

"Catastrophic and life-threatening flooding" is forecast to continue across the majority of Puerto Rico, the National Hurricane Center said.

After slamming into Puerto Rico on Sunday, Hurricane Fiona moved into the Dominican Republic on Monday morning. The National Hurricane Center said on Monday that "hurricane conditions" were expected to continue over portions of the Dominican Republic.

This story has been updated with new information.