Police say a man told them she was in a car with him around 1 a.m. Tuesday, when she became distraught.
According to authorities, the man told them she made suicidal statements, jumped out of the car and walked into traffic.
That's when the big rig hit and killed her. She has not been identified.
The fatal crash shut down all mainlanes of the freeway southbound at Scott Street, but the freeway in that direction has since reopened.
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