The National Transportation Safety Board says an Amtrak train that derailed Monday morning, spilling rail cars onto a highway below and killing three people outside Seattle, Wash., was going 80 km/h above the speed limit.

Bella Dinh-Zarr, an NTSB board member, said at a news conference late Monday night that information from the event data recorder in the rear locomotive provided information about the train's speed.

Dinh-Zarr said the train was travelling 128 km/h in a 48 km/h zone.

She said it's not yet known what caused the train to derail and that "it's too early to tell" why it was going so fast, but federal investigators will likely be on scene for a week or more.

There were 80 passengers and five crew on the train when it derailed and pulled 13 cars off the tracks. More than 70 people were taken for medical care — including 10 with serious injuries.

The train was making the inaugural run on a new route as part of a $180.7-million US project designed to speed up service by removing passenger trains from a route along Puget Sound that's bogged down by curves, single-track tunnels and freight traffic.​

Train Derailment - Crews lifting one of the damaged rail cars. <a href="https://t.co/K2i4nTyeD3">https://t.co/K2i4nTyeD3</a> —@wspd5pio

Positive train control — the technology that can slow or stop a speeding train — wasn't in use on this stretch of track, according to Amtrak's president and co-chief executive, Richard Anderson.

Anderson, speaking at a news conference Tuesday evening, was asked about positive train control and the route but offered little detail, citing the NTSB's ongoing investigation.

He spoke in favour of the technology overall, saying he's a "huge believer" in positive train control.

"There's no one that wants positive train control more than Amtrak."

Regulators have been pressing railroads for years to install such technology, and some have done so, but the deadline has been extended repeatedly at the industry's request and is now set for the end of 2018.

Anderson, who spent decades working in the aviation industry, said Amtrak is co-operating with investigators and working to support the families of the people who died in the derailment.

He said it's "not acceptable" that Amtrak is involved in these kinds of accidents.

"We're terribly sorry to the people that are involved."

In 2015, an Amtrak train in Philadelphia was travelling at twice the 80 km/h speed limit as it entered a sharp curve and derailed. Eight people were killed and more than 200 were injured when the locomotive and four of the train's seven passenger cars jumped the tracks. Several cars overturned and ripped apart.

Stretch of track under scrutiny

A track chart prepared by the Washington State Department of Transportation shows the maximum speed drops from 128 km/h to 48 km/h for passenger trains just before the tracks curve to cross Interstate 5, which is where the train went off the tracks.

The chart, dated Feb. 7, was submitted to the Federal Railroad Administration in anticipation of the start of passenger service along a new bypass route that shaves off 10 minutes for the trip between Seattle and Portland, Ore.

Aerial and ground footage show the destruction in Pierce County, south of Seattle, after an Amtrak train en route to Oregon crashed on Monday morning. 0:56

Kimberly Reason with Sound Transit, the Seattle-area transit agency that owns the tracks, said speed signs are posted three kilometres before the speed zone changes and just before the speed zone approaching the curve.

Eric Corp, a councillor for the small city of DuPont, Wash., near the derailment, said he rode the train with about 30 or so dignitaries and others on a special trip Friday before the service opened to the public Monday.

"Once we were coming up on that curve, the train slowed down considerably," he said, adding that "in no way did it make me feel like we were going too fast."

'Failing' safety culture

Just last month, the NTSB chairman issued a scathing critique of Amtrak's culture, saying a future breakdown was likely, and the board made nine safety recommendations.

"Amtrak's safety culture is failing and is primed to fail again, until and unless Amtrak changes the way it practises safety management," Robert Sumwalt said on Nov. 14.

Here is a different view of one of the train cars that’s being towed away after yesterday’s horrific derailment <a href="https://t.co/Ie6uQ3WkHm">pic.twitter.com/Ie6uQ3WkHm</a> —@briarstewart

Sumwalt's statement was made in conjunction with the NTSB's findings into a fatal Amtrak accident in April 2016 in Pennsylvania that it said was caused by "deficient safety management across many levels of Amtrak and the resultant lack of a clear, consistent and accepted vision for safety."

An Amtrak train struck a backhoe tractor on railroad tracks in Chester, Penn., killing two maintenance workers and injuring 41.

This is the curve that the train was on when it derailed <a href="https://twitter.com/hashtag/amtrak?src=hash&ref_src=twsrc%5Etfw">#amtrak</a> <a href="https://t.co/5YQpRAqw8K">pic.twitter.com/5YQpRAqw8K</a> —@briarstewart

Anderson also told reporters on Monday that Amtrak took NTSB recommendations from investigations "very seriously" and was continuing to make investments that the board recommended.

Amtrak said in a memo to employees in November that was seen by Reuters that it had been "transforming our safety culture" since the Pennsylvania incident and had made numerous reforms, including to communication, training, safety efforts and creating a team that conducts safety audits. It also expanded drug and alcohol testing.

Legal challenge

A community along the new rail line had tried to stop the project on grounds higher-speed passenger trains would endanger pedestrians and motorists.

The city of Lakewood, just north of the crash site, went to court in 2013 to stop the project.

Opponents said the route would expose car and pedestrian traffic to faster trains at more than a half-dozen street-level crossings in Lakewood.

City officials asserted the state transportation department's environmental review of the new route was inadequate and failed to consider traffic, neighbourhood and other impacts.

In March 2014, a judge dismissed the lawsuit and the track upgrade moved forward.