At least three people were killed Saturday afternoon when an Amtrak train that runs between Seattle and Chicago derailed in north-central Montana, toppling several cars onto their sides, authorities said.

The westbound Empire Builder train derailed about 4 p.m. near Joplin, a town of about 200, Amtrak spokesman Jason Abrams said in a statement. The accident scene is about 150 miles (241 kilometers) northeast of Helena and about 30 miles (48 kilometers) from the border with Canada.

Liberty County sheriff’s dispatcher Starr Tyler told The Associated Press that three people died in the derailment. She did not have more details. Amtrak confirmed the deaths and said there were multiple injuries.

“We are deeply saddened to learn local authorities are now confirming that three people have lost their lives as a result of this accident,” Abrams said.

The train had about 141 passengers and 16 crew members onboard, Abrams said. The train had two locomotives and 10 cars, eight of which derailed, he said.

Megan Vandervest, a passenger who was going to visit a friend in Seattle, told The New York Times that she was awakened by the derailment.

“My first thought was that we were derailing because, to be honest, I have anxiety and I had heard stories about trains derailing,” said Vandervest, who is from Minneapolis. “My second thought was that’s crazy. We wouldn’t be derailing. Like, that doesn’t happen.”

She told the Times that the car behind hers was tilted, the one behind that was tipped over, and the three cars behind that “had completely fallen off the tracks and were detached from the train.”

Speaking from the Liberty County Senior Center, where some passengers were being taken, Vandervest said it felt like “extreme turbulence on a plane.”

Residents of communities near the crash site quickly mobilized to help the passengers.

Between 50 and 60 passengers were brought to a local school where they were assisted with food and water. A grocery store in Chester, about 5 miles (8 kilometers) from the derailment, and a nearby religious community reportedly provided food.

The passengers were taken by buses to hotels in nearby Shelby.

The National Transportation Safety Board will send a 14-member team, including investigators and specialists in railroad signals and other disciplines, to investigate the crash, spokesman Eric Weiss said.

Weiss said the derailment occurred around 3:55 p.m. and no other trains or equipment were involved. The train was traveling on a BNSF Railway main track at the time, he said.

Photos posted to social media showed rail cars on their sides and passengers standing alongside the tracks, some carrying luggage. The images showed sunny skies, and it appeared the accident occurred along a straight section of tracks.

Amtrak said that because of the derailment, the Sunday westbound Empire Builder will terminate in Minneapolis, and the Sunday eastbound Empire Builder train will originate in Minneapolis.

Allan Zarembski, director of the University of Delaware’s Railway Engineering and Safety Program, said he didn’t want to speculate but suspected the derailment stemmed from an issue with the train track or equipment, or a combination of both.

Railways have “virtually eliminated” major derailments by human error after the implementation of positive train control nationwide, Zarembski said.

“I would be surprised if this was a human-factor derailment,” Zarembski said.

Depending on how complex the cause of the derailment was, NTSB findings may take months, he added, as investigators must interview witnesses and sift through the pile-up and damage to collect evidence and then send samples off for further testing.