Authorities are investigating a serious car crash that blocked a Cobb County interstate for nearly an hour Thursday afternoon.

The crash happened in the northbound lanes of I-575 between I-75 and Barrett Parkway about 4 p.m. Georgia Department of Transportation cameras showed a mangled silver car blocking the interstate.

Authorities blocked both northbound lanes of I-575 while responding to the crash. A HERO unit moved the damaged car to the right shoulder of the road at 4:45 p.m., and the left lane was reopened shortly after. The road was completely reopened by 6 p.m.

It is not clear if any other vehicles were involved in the crash or if the incident resulted in injuries.

Heavy delays remain in the area. Drivers are urged to use U.S. 41.

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