A derailed train has shut down I-5 south of Seattle. (WSDOT Photo)

An Amtrak train derailed off of a bridge south of Seattle Monday morning, blocking all lanes of Interstate 5, according to the Washington State Department of Transportation.

The train derailed on the Mounts Road overpass in DuPont, Wash. about 50 miles outside of Seattle.

Update 9 a.m. The Pierce County Sheriff’s department told media on the scene that at least three passengers on the train were killed in the accident and several motorists were injured.

Update 9:30 a.m. Amtrack said there were about 78 passengers and five crew members on board the train that derailed.

Update 10:30 a.m. Washington Gov. Jay Inslee declared a state of emergency in Pierce and Thurston counties Monday. State emergency resources will go toward a coordinated response to the accident.

Update 1:00 p.m. Washington State Patrol says 13 train cars were derailed in the accident, hitting five vehicles and two trucks on the freeway below the bridge.

Amtrak says it was train No. 501, which was making its inaugural trip from Seattle to Portland, in an update on the company’s website Monday morning. The company is advising people with concerns about loved ones to call 800-523-9101.

Officials in nearby Lakewood have been voicing concerns about Amtrak’s new high-speed rail plan between Tacoma and Olympia, which launched Monday. Two weeks ago, Lakewood Mayor Don Anderson told KOMO News that it was only a matter of time before the new high-speed trains killed someone, though he was not talking specifically about derailments. Anderson was most concerned about crossings and pedestrian safety.

“Come back when there is that accident, and try to justify not putting in those safety enhancements, or you can go back now and advocate for the money to do it because this project was never needed and endangers our citizens,” Anderson told KOMO.

President Donald Trump weighed in on the incident on Twitter Monday morning.

However, as The Seattle Times notes, today was the inaugural trip of the new $181 million Point Defiance Bypass project. That initiative was federally funded.

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