Crash happened near Paxton Street in Swatara Township at approximately 5:45 p.m., according to PennDOT.
The crash involved lowboy semi-trailer and construction equipment which hit the bridge, according to PennDOT.
There is lane restriction in the northbound lane of I-83 and on Paxton Street while crews work to determine if the bridge is safe, according to PennDOT.
The traffic was backed up for three exits about hours after the crash, according to PennDOT traffic cameras.
Editor's Note: This originally was published in correctly stating the cause occurred on interstate 81 citing PennLive.
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