A "duck boat" tour vehicle and a charter bus carrying foreign college students collided on a busy Seattle bridge Thursday, killing four people and sending dozens to hospitals.
The collision happened on the Aurora Avenue Bridge, which carries one of the city's main north-south highways over a lake.
At least 12 people were in critical condition, and many others suffered lesser injuries, Fire Chief Harold Scoggins said.
There was no immediate word about the cause of the crash, which involved a military-style tour bus that can also be operated on water. Initial reports described the accident as a head-on collision.
A driver who was behind the duck boat said the tour bus and duck boat were headed in opposite directions.
Brad Volm of Philadelphia said the amphibious vehicle swerved in front of him. The left front tire of the duck boat appeared to lock up, and the vehicle swerved into the oncoming charter bus, he said.
Witnesses described hearing a loud screech and then seeing injured people lying on the pavement or wandering around in a daze.