A New York commuter train that derailed on the weekend killing four people and injuring 63 others was travelling at a speed of 82 miles per hour -- nearly three times faster than the recommended limit -- when it veered off the tracks along a curve, authorities said.
"Preliminary information shows that the train was travelling at approximately 82 miles per hour as it went into a 30 miles an hour curve," National Transportation Safety Board member Earl Weener told reporters.
Weener said the investigation into the crash is ongoing and it was yet soon to say whether the derailment was caused by human error or faulty equipment.
The throttle was engaged until six seconds before the locomotive came to a stop on its side, and the brakes were fully applied only five seconds before, Weener said.
That is "very late in the game."
Weener said the investigation would focus primarily on not only when the brakes were applied but also why the train was travelling at such a speed that it required an emergency manoeuvre.
He said it was unclear if the engineer of the train, who is a 20-year veteran, hit the brakes and they failed, or that he tried to slow down when it was too late.
"The question is: Was this human error or faulty equipment? And the answer is at this point in time we can't tell. We do know that two minutes before the curve the train was going at 60 miles per hour and had accelerated then up to 82 miles per hour prior to entering the curve," Weener said.
Investigators have recovered the black box of the train as well as data recorders and are also interviewing the train's engineer and conductor and three crew members.
The engineer of the train has been identified as William Rockefeller, who had been injured in the crash and will continue to be interviewed by authorities over the next few days.
Weener said drug and alcohol tests have been conducted but the results were not yet available.
Rockefeller’s cellphone has also been recovered as part of the investigation, Weener added. The authorities are also examining surveillance video from a bridge near the site.
A Metropolitan Transportation Authority official said Rockefeller has told emergency medical workers that he "dumped the brakes" when he saw that the train was heading into the curve at a fast speed.
The curve where the train derailed is in a slow-speed area, where the speed limit is 30 mph.
The area just before the curve is a 70 mph limit and by every standard the train was over-speeding.
"The zone leading up to the curve was an 70 miles an hour zone. At 82 miles an hour, the train was in excess of that speed," Weener said.
New York Senator Charles Schumer said any conclusions about the cause of the excessive speed would be "premature."
"When I heard about the speed, I gulped. It kind of takes your breath away," Schumer said at the press conference.
"There's one obvious point here, which is that the train did make nine stops before coming to this curve," he added.
"So clearly the brakes were working a short time before it came to this curve."
"It's beyond frightening. It's harrowing," said Connecticut Senator Richard Blumenthal.
The injured passengers were taken to a number of local hospitals. Of the 63 people injured, 11 were critical.
The early morning Metro-North train from Poughkeepsie bound for Grand Central in Manhattan derailed while rounding a bend just north of the Spuyten Duyvil station in a wooded area where the Hudson and Harlem rivers meet and footage from the crash site showed that one rail car was lying toppled near the edge of the water.
Four cars on the seven-car train turned on their side, throwing unsuspecting passengers into the air.
The train had about 120 passengers on board and was not scheduled to stop at the Spuyten Duyvil station.
Weener said investigators would be carefully reviewing all data to review the functioning of the brakes throughout the trip and extensive investigations would continue for the next 7-10 days.
New York Governor Andrew Cuomo said earlier that he feels the accident was speed-related.
"Three options are on the table," Cuomo said on the TODAY show at NBC News.
"Problem with the track, equipment problem or operator error. I’m not an expert in this field. Working with the experts over the past day, I think it is going to be speed-related. It was a tricky turn on the system, but it is a turn that has been there for decades."
The derailment has impacted daily commutes of thousands of people who use the Metro-North train service to get into Manhattan for work from New York's suburbs.
Head of the train employees union Association of Commuter Rail Employees Anthony Bottalico said the engineer has an "impeccable" job record and is cooperating with investigators.
Bottalico said Rockefeller has "never been disciplined on his job on the railroad" and was scheduled to meet with NTSB officials. "He's very traumatised," Bottalico said.
"He's devastated by the loss of life, by the injuries to the passengers and his fellow crew members, and he's extremely upset about all of it."
Weener said that the tracks have been given to Metropolitan Transportation Authority for repair works.
Crews were working overtime to lift the derailed cars and clearing the scene to return the tracks to service.