One southbound lane of Fremont Boulevard is open.
Traffic investigators responded to the collision at 3:30 a.m. at the intersection of Fremont Boulevard and Darwin Drive, police said.
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The collision involved two vehicles, each carrying two people.
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Police say a black Toyota Yaris was making a left-hand turn from southbound Fremont Blvd onto eastbound Darwin Drive when it collided with a blue Chevy Malibu traveling northbound on Fremont Boulevard.
The passenger in the black Yaris was pronounced dead at the scene. Police say the victim was an 18-year-old female. The driver of the Yaris was the victim's mother, she suffered major but non-life threatening injuries.
The driver of the Malibu was a 23-year-old adult male and the right front passenger, a 25-year-old adult male, are both Union City residents. The two men sustained minor injuries and were transported to local hospitals.
Investigators tell ABC7 News that they are looking into whether alcohol played a role in the collision. No arrests have been made.
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