A passenger train has crashed in the Bronx area of New York City, and US media are reporting that at least four people have been killed.
Dozens are reported to have been injured as several of the Metro-North train's carriages came off the tracks.
The Metropolitan Transportation Authority (MTA) said none of the carriages had gone into the adjacent Hudson or Harlem rivers.
The train was the 05:54 from Poughkeepsie to Grand Central Station.
The Fire Department of New York says the derailment occurred at 07:20 near Spuyten Duyvil station, causing "multiple injuries", and that 130 firefighters were on the scene.
Metro-North is a rail service that serves commuters from New York City's northern suburbs. It is not part of the New York City subway system.
Hudson Line services had been suspended, the MTA said.
New York state Governor Andrew Cuomo is reported to have arrived at the scene.