UPDATE: Three people were killed and around 100 were taken to hospitals Monday after an Amtrak train derailed while traveling on the first day of a new route outside Tacoma, Washington.

"There have been multiple casualties as a result of the Amtrak derailment near Tacoma, Washington," Pierce County spokesman Ed Troyer said of the 7:40 a.m. incident. "The casualties include multiple injuries and fatalities."

Officials have confirmed that none of the motorists on the interstate were killed.

Monday afternoon, the National Transportation Safety Board said that it will be putting a team together to investigate the cause of the crash.

78 passengers and five crew members were on the train at the time of the crash.

Passenger Chris Karnes told MSNBC that the train derailed while traveling on tracks that are part of a new route in and out of Tacoma. The southbound train had just passed the city of Dupont and was traveling about 70 mph, he said.

"At a certain point the train started to wobble a little bit and the next thing that we knew we were down in a ditch," Karnes, member of a local transportation advisory group, said. "The train had crumpled."

He spoke as a rescue operation was still underway, describing inured people being lifted out of the wreckage.

Washington State Department of Transportation tweeted a picture of the derailment at 7:45 a.m. PST, showing what appeared to be a car on its side over a highway lane.

"All SB lanes of I-5 blocked near Mounts Road in Pierce County due to derailed train car. Avoid area!" the tweet said.

Following the incident, Amtrak tweeted that it had been made aware of the incident.

"Amtrak is aware of an incident with Train 501, Cascades service from Seattle to Portland. Emergency services are on the scene and Amtrak management is responding," the company said in a statement.

"Amtrak service south of Seattle is temporarily suspended. Service from Seattle to points north and east is continuing to operate."

The derailment happened between Olympia and Tacoma on a newly established Amtrak route aimed at adding more frequent and faster service Seattle and Portland, part of an $800 million project called the Cascades High-Speed Rail Capital Program.

This is a developing story, please check back for updates.