As of 4 p.m., the crash has been cleared.
As of 2 p.m., traffic is backed up for about three miles, according to VDOT.
A crash has caused a 2.5-mile backup on I-81N in Montgomery County, according to VDOT.
Authorities said the crash happened near mile marker 124.
As of 12:26 p.m., the northbound left shoulder, left lane and right shoulder are closed.
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