(WUSA9) -- The origin of the debris that caused a dozen flat tires on the Outer Loop of I-495 after River Road on Monday morning is unknown. Maryland State Police are still trying to determine what left the debris in the area.
Sky 9 was over the scene early Monday morning and captured photos of several cars pulled over on the shoulder.
There were delays on the Outer Loop. Maryland State Police say the debris appears to be clear now.