The National Transportation Safety Board said it expected to continue investigating the accident for at least the next week, with the focus on track conditions, signaling, mechanical equipment and the train crew’s performance.

Four people were killed with 63 others injured on Sunday when the Metro-North passenger train derailed in the Bronx.

Speaking at the scene of the crash, New York Governor Andrew Cuomo said officials believed everyone at the site had been accounted for and that the train operator was among the injured.

The train, heading southbound from Poughkeepsie to New York's Grand Central Station, derailed at around 7:20 a.m. (1220 GMT) by Palisade Avenue near the Spuyten Duyvil railroad station, the Fire Department of New York (FDNY) said.

Metropolitan Transportation Authority (MTA) spokesperson Marjorie Anders said the curve where the accident occurred was in a slow speed area. She said the black box onboard should be able to tell how fast the train was traveling at the time of the crash.

Photos taken of the scene of the accident show several cars on their side, with one just feet from the edge of the water where the Harlem River meets the Hudson.

Sunday marked the end of America's Thanksgiving holiday, which annually sees many people in mass transit as they travel home to their families across the United States for the long weekend.

hc,rc/lw (Reuters, AFP, AP, dpa)