A powerful coastal storm knocked down trees and left more than 600,000 homes without power in the northeastern United States on Wednesday.

The state of Massachusetts was the hardest hit, with 495,000 homes without power as of 9:00 am (1300 GMT), according to the poweroutage.us website.

The National Weather Service called the situation dangerous and warned of hurricane-type gusts of wind and many uprooted trees.

“Travel is not recommended,” said the NWS office in Boston.

Rhode Island was also badly affected, with 96,000 homes without electricity.

The NWS said the situation should improve toward the end of the day and that the storm “will move farther offshore tonight.”

It drenched the New York region on Monday night and Tuesday before packing winds of almost 100 mph overnight into Wednesday as it headed north.

The storm forced the closure of dozens of schools in New England and brought down power lines and branches, littering some roads with debris.

In Barnstable, Massachusetts police rescued a woman from her car after a tree fell on it, local media reported.

In the coastal town of Duxbury, south of Boston, the fire brigade said it responded to 90 calls in 12 hours due to the storm. (AFP)

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