Update: 4 dead, 7 critically injured as bus, duck tour vehicle collide in Seattle

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Two people are dead and 9 injured in a Seattle Ride the Ducks tour boat that collided with a bus on Thursday, Sept. 24, 2015, according to Seattle Fire Department tweet. **Embargo Seattle, WA**

SEATTLE — Two people were killed and at least nine were critically injured when a tour bus and a duck boat tourist vehicle collided Thursday morning in Seattle, the city’s fire department tweeted.

Two more people were pronounced dead a short time later.

“All patients extricated,” the Seattle Fire Department said.

The department said that about 50 people had been evaluated for injuries after the crash.

It was not immediately clear how many of those people were hurt or how serious their conditions might be.

A nursing supervisor at Harborview Medical Center in Seattle did tell CNN that hospital alone is expecting 25 patients with unknown injuries.

Seattle police tweeted that Aurora Bridge between downtown Seattle and the Fremont neighborhood was closed in both directions, to both pedestrian and vehicle traffic.

Photos from the scene showed the two wrecked vehicles being surrounded by scores of firefighters — with about 90 first responders in all rushing to the scene, according to Lt. Sue Stangl from the Seattle Fire Department.

Stangl told reporters it was not immediately known what caused the crash.

North Seattle College issued a statement since some of its students were involved in the accident.

“At approximately 11:15 a.m., students and staff members with North Seattle College’s International Program were involved in a vehicle accident while traveling on the Aurora Bridge.

The accident occurred when a chart bus traveling with the students collided with a Ride the Ducks tour vehicle. Students and employees who were involved in the accident are being transported to campus where counselors will be on hand to support them.

We are working to learn the status of all students and employees involved in the accident and will provide an update as soon as possible.”