Welcome to the BBC's latest updates from the Metro-North passenger train derailment in New York City. The train derailed in the Bronx area, prompting a major emergency services response amid reports of "multiple injuries". Five of the Metro-North train's seven carriages came off the tracks, New York's transport authority said.
The Metropolitan Transportation Authority police say the train derailed at about 07:20 local time on Sunday near the Spuyten Duyvil station in the Bronx.
None of the cars entered the Hudson or Harlem rivers.
The commuter train was bound for New York's Grand Central Station, the city's Fire Department said.
US media are reporting that at least four people have been killed.
Passenger Frank Tatulli, who suffered head and neck injuries, tells Eyewitness News, reported by ABC, he thought the train was travelling at a higher rate of speed than it normally does.
NYPD canine officers are searching the woods with dogs for passengers who may have been thrown from the carriages on impact.