The accident happened at about 11 a.m. on Mill Road in Valley Stream.
Witnesses said the minivan was struck and then rolled over several times until it came to rest on its side.
Two people had to be cut out of the wreckage.
The road was littered with car parts and broken glass. The cause of the crash is not yet known.
The speed limit in the area is 30 miles an hour, but residents say it is not unusual to see cars going by at 50 or 60 miles an hour.
Mill Road was closed for about six hours after the accident.
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