Maryland State Police said vehicles were still using the northbound shoulder at 9 a.m. Thursday to get by the accident just north of the Route 109 interchange.

They say the tractor-trailer apparently hit some debris and then struck a guardrail before overturning shortly after 4 a.m.

Images from WUSA-TV show hundreds of cans on the highway and median, with some liquid spilled on the pavement.

Police say a hazardous materials team was called in because of a fuel tank rupture.

It’s unclear when the roadway will be completely reopened.

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