A crash in Marysville on southbound I-5 at SR 529 blocked the left lane and backed up traffic.
KIRO 7 Traffic Anchor Rachel Calderon says it happened at about 6:30 a.m. Thursday and there were multiple aid vehicles at the scene.
Traffic was backed up for 4 miles.
It is not yet known if anyone was hurt.
Calderon says the commute from Arlington to Everett was 36 minutes -- about 22 minutes longer than usual because of the crash.
The crash was cleared at about 7:15 a.m.
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