Rescue teams worked Sunday to reopen roads to remote communities in Dominica after Tropical Storm Erika caused flooding and mudslides that killed at least 20 people and left more than 50 missing on the Caribbean island.

"Access by road to these communities is impossible," Prime Minister Roosevelt Skerrit said. These towns "are cut off from the rest of the country."

In a national address late Saturday, Skerrit said he was declaring disaster status for nine local areas.

Erika whipped the island for more than five hours on Wednesday, bringing strong winds and intense rain that provoked flooding and landslides. Hundreds of homes were destroyed.

Crews were using heavy equipment sent by the governments of Venezuela, Martinique and Guadalupe. Hundreds of men worked Sunday to reopen the country's main airport, where mud and debris impeded operations, Skerrit said.

Skerrit appealed for international aid and estimated that damage from the storm could set the country's development back two decades.

In Haiti, the storm killed at least one person in a suspected landslide. Four others died when a truck hit a bus during the downpour.