An Amtrak passenger train derailed on a bridge over a major highway in Washington state on Monday morning, sending part of the train crashing down onto Interstate 5 and killing several passengers, authorities said. A spokesman for the local sheriff's office, Ed Troyer, told reporters at the scene there were "multiple" deaths. He said no motorists were killed, though some were injured when part of the train struck cars. Amtrak passenger Chris Karnes told local news outlet KIRO 7 that passengers were forced to kick out train windows in order to escape because emergency doors were not functioning properly following the derailment. "We had just passed the city of DuPont and it seemed like we were going around a curve," Karnes said. "All of a sudden, we felt this rocking and creaking noise, and it felt like we were heading down a hill."The next thing we know, we're being slammed into the front of our seats, windows are breaking, we stop, and there's water gushing out of the train. People were screaming." The derailment occurred on the first day that Amtrak trains began using a new track between the cities of Tacoma and Olympia, part of a project to reduce travel time. The new route takes trains along Interstate 5, eliminating a major choke point for passenger trains in Tacoma and allowing trains to reach speeds of 127km/hr, the department has said. It was not immediately clear whether the derailment, which came during a busy travel time one week before the Christmas holiday, was connected to the new route. Amtrak confirmed its train was involved and said "some injuries" had been reported but did not offer further details. The train derailed around 7.30am local time in DuPont. A photograph posted by a Washington State Police spokeswoman showed an upside-down train car partially crushed on the highway, with a second car dangling off the overpass. About 70 people were aboard the train, local news media reported, citing the state transportation department. Authorities warned drivers to avoid the area, and the southbound lanes remained closed. "Thank you to the first responders on the scene. We're praying for everyone on board the train, and ask everyone to hold them in your thoughts," Washington Governor Jay Inslee wrote in a Twitter message. The train had been scheduled to leave Seattle at 6am and arrive in Portland, Oregon, at 9.20am, according to an Amtrak timetable. Monday was the first day that Amtrak offered a 6am departure on its Amtrak Cascades line as part of the rerouting project. The mayor of one of the towns through which the rerouted trains travel warned earlier this month that the high-speed trains were dangerously close to cars and pedestrians. "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," Lakewood Mayor Don Anderson told transportation officials in early December, according to Seattle's KOMO News.