A major wreck involving two cars and two box trucks caused major delays on both sides of the Beltway near the American Legion Bridge in Maryland. Reports state that backups went 7 miles in each direction, and lasted about 4 hours.
The Montgomery County Fire and Rescue Service stated that a box truck crash and landed on top of two cars. Another box truck was also involved in the collision and was leaking fuel afterwards. The drivers of the two trucks reportedly sustained minor injuries.
Cleanup involved multiple emergency response teams as well as hazmat crews that helped clean up the leaking fuel. No further details have yet been released as to what exactly caused the crash.
Source: http://wtop.com/local/2016/11/crash-closes-outer-loop-of-beltway-at-legion-bridge/slide/3/