UPDATE 7:34 PM: Based on witness reports and the above photo, it sounds like they're talking about this bridge, which was built in 1955 and which Bridgehunter.com says got a satisfactory rating back in 2010:
Inspection (as of 08/2010) Deck condition rating: Satisfactory (6 out of 9) Superstructure condition rating: Fair (5 out of 9) Substructure condition rating: Satisfactory (6 out of 9) Appraisal: Functionally obsolete Sufficiency rating: 57.4 (out of 100)
UPDATE 8:22 PM: Marcus Deyerin on Twitter is saying that two people are being extracted from a truck that's in the water at the moment. Authorities are asking people to stop coming to the scene, as they're getting in the way. Also, they're asking residents of Skagit to stay off the phone if they can, as lines are getting tied up.
UPDATE 8:28 PM: Rescuers in boats are at the scene. I've put another photo after the jump.
UPDATE 8:30 PM: On Twitter, Skagit Valley Herald reporter Gina Cole says: "Stretcher with second person pulled from river. Unsure if person is alive, but no applause from onlookers this time when they reached land." KOMO says one person has been pulled from a car and two have been rescued from a truck. Here's a KOMO live feed.
UPDATE 8:35 PM: I've heard from multiple eyewitnesses on different news livestreams that the collapse appeared to happen because a wide load truck struck a beam on the bridge. We're a long way from discovering the reason for all this, though.
UPDATE 8:58 PM: The Seattle P.I. says the bridge was declared "safe and sound" by Washington's Department of Transportation in 2008.