Suffolk County police say the car went airborne after losing control on the Expressway Drive North service road of the Long Island Expressway before crashing into a building in Brentwood around 8 p.m. Thursday.
Police say the car was going very fast, failed to make the turn and went off the road.
The car then flipped and hit the back of the 7-Eleven near Wicks Road.
The most seriously injured victim was the pregnant passenger, who was taken by helicopter to Stony Brook University Hospital. The male driver and a little girl were both taken to Southside Hospital.
The crash is still under investigation.
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