By Steve Beck, Al Novack

PHILADELPHIA (CBS) — A reported drive-by shooting temporarily shut down a heavily-traveled bridge in Philadelphia early Thursday morning.

The shooting happened shortly before 5 a.m. in the westbound lanes of the Passyunk Avenue Bridge, which spans the Schuylkill River.

According to investigators, shots were fired from inside a car that was traveling in the westbound lanes of the bridge.

It was not immediately known if there was an intended target, but investigators said they found 10 shell casings in the area.

The bridge was fully reopened at about 6 a.m.

There were no reports of any injuries.

The investigation is ongoing.

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