UPDATE 8:00 a.m. All lanes have reopened.

UPDATE 7:45 a.m. A tractor trailer collision that requires response from county Hazmat units has closed the outerloop of the Beltway between Bradley Boulevard and River Road this morning.

The closure is causing back ups on the Beltway back to Wheaton and on southbound I-270 up to Rockville. Police are diverting I-270 traffic onto Old Georgetown Road.

MCFRS Assistant Chief Scott Graham, a spokesman, said the incident occurred shortly before 7 a.m. this morning.

All lanes of the outer loop are closed, which has already caused significant delays.

Photo via TrafficLand.com