SAN JUAN, Puerto Rico >> Rescuers fanned out to reach stunned victims today after Hurricane Maria ravaged Puerto Rico, knocking out electricity to the entire island and triggering landslides and floods.

The extent of the damage is unknown given that dozens of municipalities remained isolated and without communication after Maria hit the island Wednesday morning as a Category 4 storm with 155 mph winds, the strongest hurricane to hit Puerto Rico in over 80 years.

Uprooted trees and widespread flooding blocked many highways and streets across the island of 3.4 million residents, creating a maze that forced drivers to go against traffic and past police cars that used loudspeakers to warn people they must respect a 6 p.m. to 6 a.m. curfew imposed by the governor to ensure everyone’s safety. People resorted to rafts and kayaks to get around because flooding made many roads remained impassable.

“This is going to be a historic event for Puerto Rico,” said Abner Gomez, the island’s emergency management director.

President Donald Trump approved a federal disaster declaration for Puerto Rico.

Previously a Category 5 with 175 mph winds, Maria hit Puerto Rico as the third-strongest storm to make landfall in the U.S., based on its central pressure. It was even stronger than Hurricane Irma when that storm roared into the Florida Keys earlier this month.

In the capital of San Juan, towering eucalyptus trees fell nearly every other block over a main road dotted with popular bars, restaurants, and coffee shops, some of which were damaged. Outside a nearby apartment building, 40-year-old tourism company operator Adrian Pacheco recounted how he spent eight hours in a stairwell huddled with 100 other residents when the hurricane ripped the storm shutters off his building and decimated three balconies.

“I think people didn’t expect the storm to reach the point that it did,” he said. “Since Irma never really happened, they thought Maria would be the same.”

Hurricane Irma sideswiped Puerto Rico on Sept. 6, leaving more than 1 million people without power but causing no deaths or widespread damage like it did on nearby islands. Maria, however, blew out windows at some hospitals and police stations, turned some streets into roaring rivers and destroyed hundreds of homes across Puerto Rico, including 80 percent of houses in a small fishing community near the San Juan Bay, which unleashed a storm surge of more than 4 feet.

“Months and months and months and months are going to pass before we can recover from this,” Felix Delgado, mayor of the northern coastal city of Catano, told The Associated Press.

The slow slog back to normalcy was in evidence today, however, as residents removed storm shutters and lines began forming at the few restaurants with generator power. The sound of chainsaws and small bulldozers filled the post-storm silence that had spread across San Juan as firefighters removed trees and lifted toppled light posts.

Some neighbors pitched in to help clear the smaller branches, including Shawn Zimmerman, a 27-year-old student from Lewistown, Pennsylvania who moved to Puerto Rico nearly two years ago.

“The storm didn’t bother me,” he said. “It’s the devastation. I get goosebumps. It’s going to take us a long time.”

Maria has caused at least 19 deaths across the Caribbean, including more than 15 in the hard-hit island of Dominica and two in the French Caribbean territory of Guadeloupe.

Dominica Prime Minister Roosevelt Skerrit cried as he spoke to a reporter on the nearby island of Antigua.

“We have buried in excess of 15 people,” he said. “It is a miracle there were not hundreds of deaths.”

Puerto Rico’s governor told CNN one man died after being hit by flying debris. No further details were available, and officials could not be immediately reached for comment.

Maria had briefly weakened to a Category 2 storm before re-strengthening to Category 3 status early today with maximum sustained winds of 115 mph. According to the National Hurricane Center in Miami, the storm was centered about 105 miles east-northeast of Puerto Plata, Dominican Republic, and moving northwest at 9 mph. The eye of the storm is expected to approach the Turks and Caicos Islands and the southeastern Bahamas late today and early Friday.

The hurricane was still dumping rain overnight Wednesday in Puerto Rico, where crumbled red roof tiles lay scattered across many roads, and curious residents sidestepped and ducked under dozens of black power lines still swaying in heavy winds. But they posed no danger: Maria caused an island-wide power outage, with officials unable to say when electricity would return.

Puerto Rico’s electric grid was crumbling amid lack of maintenance and a dwindling staff even before the hurricanes knocked out power. Many now believe it will take weeks, if not months, to restore power.

Edwin Rosario, a 79-year-old retired government worker, said an economic crisis that has sparked an exodus of nearly half a million Puerto Ricans to the U.S. mainland will only make the island’s recovery harder.

“Only us old people are left,” he said as he scraped a street gutter in front of his house free of debris. “A lot of young people have already gone … If we don’t unite, we’re not going to bounce back.”