An Amtrak train derailed Monday morning in Washington state. This was the first ride for a new high-speed service linking the cities of Olympia and Tacoma. The cause of the derailment is not yet known, though at least one source has confirmed people have died in the crash.

Amtrak Train 501 derailed shortly before 7:45 a.m. Pacific time. It came off the tracks while crossing an overpass above Interstate 5 in Pierce County, about 20 miles south of Tacoma and 15 miles east of Olympia. Photos from the scene show one of the train cars hanging off the bridge, while other derailed cars reportedly hit vehicles on the highway.

Amtrak has confirmed that 78 passengers and five crew were on board the train, which was making its first ever journey along a new inland, high-speed route designed to cut travel times between the two Washington cities by 10 minutes. The derailment occurred on part of this new section, which is a bypass route that runs along I-5.

The train’s last known speed before the derailment was 81 miles per hour, according to Amtrak’s real-time location service. This appears to be at the top end of the speeds the trains are designed to reach, as the goal of using this bypass was to have the trains operate at speeds of up to 80 miles per hour.

The extent of injuries and fatalities is not yet known. Current reporting indicates at least three passengers died in the crash, though no motorists appear to have died.

Amtrak has asked those concerned about friends or family aboard Train 501 to call 1-800-523-9101. Further service along the line has been canceled, and Washington State Police are working to divert traffic from the area.

This is Amtrak’s fifth accident since 2015, and the third to result in fatalities. An Amtrak train derailed in Philadelphia in 2015, killing eight and injuring 200. Another train struck and killed two track workers in Chester, Pennsylvania, in 2016, also injuring 41 passengers. Other Amtrak trains derailed without deaths in Halifax, North Carolina, in 2015 and Cimarron, Kansas, in 2016.

Photos via Pierce County Sheriff