A big rig truck caught fire on the northbound 5 Freeway on Tuesday afternoon, quickly becoming fully engulfed in flames and causing a huge traffic backup as authorities responded to the hazard.
NewsChopper4 was over the charred remnants of the truck cab, seen on the side of the 5 Freeway in the Newhall Pass area near Weldon Cyn Road.
The California Highway Patrol received a call about a truck on fire just after 2 p.m., which was fully engulfed by 2:23 p.m.
All lanes on the northbound side were closed by 2:49 while authorities responded to the scene.
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By 3 p.m., two lanes had been reopened. Traffic was still backed up for an estimated 10 miles as of 3:45 p.m. on Tuesday.
This is a developing story. Check back for updates.