The crash, which occurred near the eastbound fast lane and westbound left shoulder, resulted in no reported injuries, according to the Washington County Division of Emergency Services.
Montgomery County Fire and Rescue Service crews were on the scene pumping fuel from the truck's saddle tanks, with an assist from first responders out of Washington County.
The Maryland State Highway Administration was also present, awaiting a heavy tow truck to remove the wreckage.
Drivers faced lane closures in both directions, leading to heavy traffic backups in the area, officials said.
Motorists are advised to seek alternate routes while crews work to clear the scene.
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