The crash happened on Wednesday, July 1 at around 3:50 a.m. in Levittown, Nassau County Police said.
The man, also age 20, was driving the 2015 Nissan Pathfinder northbound near the Gardiners Avenue Elementary School on Gardiners Avenue when he lost control of his vehicle and struck a tree near the intersection of Harbor Lane, police say.
Both the man and woman were transported to an area hospital. The woman suffered serious trauma and was pronounced dead by hospital staff, according to police.
There appears to be no criminality at this point, police said.
The investigation is ongoing.
This is a developing story. Check back to Daily Voice.
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