The Metropolitan Transportation Authority said four or five carriages on the seven-carriages derailed close to the Spuyten Duyvil station in the Bronx, New York.
None of the cars entered the Hudson or Harlem rivers, which are adjacent.
Early reports indicate that four people have died and a further 48 are injured. This figure is expected to change.
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Buckingham Palace, London's Tower Bridge, Old Trafford and Big Ben are taking part in the event to raise awareness about climate change.
Widespread frost for most areas as temperatures dip below freezing.
Premier League clubs have agreed to pay all full-time staff the living wageof £9.15 an hour in London or £7.85 an hour outside the capital.