Officials said four migrants swam ashore and three others were rescued.

WASHINGTON — The U.S. Coast Guard is searching for 20 people missing off the coast of Florida, saying a boat carrying migrants sank as Hurricane Ian neared the peninsula.

Miami Chief Patrol Agent Walter Slosar said on Twitter on Wednesday that four Cuban migrants washed ashore on Stock Island near Key West after their boat capsized in extreme weather. He said the US Coast Guard is looking for 23 more people.

A few hours later, the US Coast Guard announced the crews saved three people about two kilometers away south of Boca Chica Key. Officials said they were taken to a local hospital with symptoms of exhaustion and dehydration.

As of Thursday, air crews continued to search reported missing.

Hurricane Ian made landfall in southwest Florida near Cayo Costa on Wednesday as a powerful Category 4 storm.

“It’s going to be a nasty nasty day, two days,” Florida Gov. Ron DeSantis said, stressing that people along Ian’s path along the coast should rush to the safest shelter and stay there.

RELATED: Cuba begins to restore light after Ian blacks out the island

About 2.5 million people were ordered to evacuate southwest Florida before the storm hit the coast with maximum winds of 150 miles per hour. The storm was heading inland, where it was expected to weaken, but residents of central Florida could still experience hurricane-force winds.

Before making its way across the Gulf of Mexico to Florida, powerful Hurricane Ian tore into western Cuba on Tuesday.

Cuban officials said they began restoring power on Wednesday Hurricane Jan knocked out power to the entire island, while devastating some of the country’s most important tobacco farms, when a severe storm hit the western tip of the island.

The Associated Press contributed to this report.

RELATED: Ian made landfall in southwest Florida as a dangerous Category 4 storm