UPDATE: All lanes have reopened.

WASHINGTON – An accident on the Inner Loop of the Capital Beltway let traffic trickle by to the left as authorities dealt with a possible fuel spill Monday night.

A tractor-trailer was overturned in the accident, which occurred just before 11 p.m. Monday, say Maryland State Police.

Initially, it blocked the Inner Loop completely before Route 450/Annapolis Road.

By 12:20 a.m., the two left lanes were getting by. The driver has critical injuries, say police.

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