By Steve Beck

PHILADELPHIA (CBS) — It was every driver’s worst nightmare on I-95 Thursday morning.

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A tire broke free from a car, went flying and struck another car.

The freak incident happened at about 8 a.m. on I-95 near the Girard Avenue exit.

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According to investigators, a car traveling in the southbound lanes lost a wheel. The wheel then rolled into the northbound lanes and struck another car.

Authorities say two people were taken to Thomas Jefferson University Hospital in unknown conditions.

The freak incident remains under investigation.

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