TRAFFIC: Serious injury crash blocks 3 lanes of I-5 after car rolls down embankment

SEATTLE -- A serious injury crash on southbound Interstate 5 near Boeing Access Road blocked three lanes of traffic Thursday morning.

The Washington State Department of Transportation tweeted about the crash around 8:30 a.m.

Two 17-year-old males were taken from a crashed vehicle. Both were transported to Harborview Medical Center, and one was in serious condition.

One state official  called the response to the crash one of the "largest I've ever seen." Police investigated the crash as a "felony collision," officers said.

There is no ETA for lanes reopening. A significant backup had formed at 9 a.m.

This story is breaking and will be updated as more information becomes available.