"We are all isolated": Days after Hurricane Fiona slammed Puerto Rico, several areas still cut off

Hurricane Fiona left dozens of families stranded across Puerto Rico after smashing roads and bridges, with authorities still struggling to reach people four days after the storm smacked the U.S. territory, causing historic flooding.

For now, government officials are working with religious groups, nonprofits and others braving landslides, thick mud and broken asphalt by foot to provide food, water and medicine for people in need, but they're under pressure to clear a path so vehicles can enter isolated areas soon.

Nino Correa, commissioner for Puerto Rico's emergency management agency, estimated that at least six municipalities across the island had areas that were cut off by Fiona, which struck as a Category 1 hurricane and was up to a powerful Category 4 early Thursday as it headed toward Bermuda.