Amtrak Passenger Train Derails in Washington State, 'Casualties Reported'

A high-speed Amtrak passenger train has derailed near Tacoma in the US state of Washington, with the Pierce County sheriff's office saying that "injuries and casualties" were reported.

While the authorities are yet to release a statement on the exact number of casualties in the accident that took place before 8 a.m. local time 64 kilometers south of Seattle, a major emergency response has been underway after the train fell off a bridge that runs above a major interstate.

The Pierce County sheriff's department's spokesman told CNN that "there were some fatalities" as a result of the accident as at least one car fell of the bridge onto the highway.

According to AP citing a US official, at least 6 people were killed and many injured after the train derailed and partially fell off the bridge while traveling from Seattle, Washington to Portland, Oregon.

Media reports indicate that first responders are treating the situation as a mass casualty incident, with several cars still hanging from the bridge.

"Multiple motorists injured on roadway, no fatalities of motorists reported," the sheriff's office stated.

Photos from the site released by social media users show that a part of the train is apparently hanging off the track.

The ongoing situation involving the Amtrak passenger train that partially fell off a bridge above a highway is "serious," according to Washington Governor Jay Inslee's Twitter statement.

"Thank you to the first repsonders on the scene," Inslee said.

According to Amtrak's statement on Twitter, there were about 78 passengers and five crew members aboard the Amtrak train 501, adding that initial reports indicate "some injuries."

CBS News reported that four of the 77 people taken to hospitals were considered "level red" patients with the most severe injuries.

All southbound lanes of Interstate 5 have been closed south of Joint Base Lewis-McChord, with drivers being warned to avoid the area.

According to Reuters citing a news release from the state's transportation department that dates back to October, the accident has occured on the first day that Amtrak trains started using a new track between the cities of Tacoma and Olympia in order to reduce travel time.