405 Freeway

A Sigalert map shows the traffic impact of a fatal crash on the northbound 405 Freeway. (SigAlert / January 22, 2014)

A fatal collision between a motorcyclist and another vehicle in West Los Angeles backed up morning commuter traffic up and down a long stretch of the 405 Freeway through the Sepulveda Pass.

The incident occurred at about 3:45 a.m. when authorities got a call that a motorcyclist and a vehicle were involved in a collision on the northbound 405 Freeway near Getty Center Drive, said California Highway Patrol Officer Jennifer Cassidy.

The female motorcyclist was pronounced dead at the scene, prompting officials to issue a Sigalert. The motorcyclist's identity was not immediately available.

[Updated, 11:30 a.m. PST Jan. 22: A spokesman with the Los Angeles County coroner’s office identified the motorcyclist as 31-year-old Fallon Naccarato of Newbury Park.]

Authorities initially closed all five lanes of the northbound roadway, and several hours later, just the far right lane had been reopened. It was unclear how long the lane closures would last but Cassidy said investigators needed time at the scene.

"Traffic backup is probably half a mile," she said.

Traffic was being diverted off the freeway at the Getty Center Drive exit to get on Sepulveda Boulevard and reenter the 405 at Skirball Center Drive.

The lane closures were also starting to affect traffic on the 101 Freeway, officials said.

[Updated, 9 a.m. PST Jan. 22: All lane closures have been lifted and the freeway is now fully open, according to the California Highway Patrol.]

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