The crash happened at about 1:04 a.m. on the southbound lanes of I-57, according to Illinois State Police.
A red Hyundai sedan was traveling northbound in the southbound lanes when it crashed into a White Dodge Durango at 147th Street.
The driver of the Hyundai then crashed into an Amtrak police squad car at 111th Street.
The Amtrak officer was not hurt and the driver of the Dodge refused treatment, according to ISP.
The driver of the Hyundai ran off on foot and left the vehicle behind.
Nobody is in custody.
The lanes were closed, but were reopened by 5 a.m.
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