M25 closed in Hertfordshire as crack found in viaduct
Part of the the M25 has been closed after a crack was discovered in a bridge.
The fault was found in a viaduct which carries the motorway over a railway line, a river and farmland near Kings Langley, Hertfordshire .
Engineers discovered it during a routine inspection on Tuesday.
The anti-clockwise stretch of the road is closed between Junctions 21a and 20, near the M1 junction. Repairs are likely to take until about 15:00 GMT.
Francis Cluett, from Highways England, said: "The crack is in one of the stiffeners in one of the beams holding up the bridge.
"It's quite small at the moment but we've really got to get that repaired now before it grows any further and creates more damage."
Traffic from the southbound M1 onto the anti-clockwise M25 is being restricted to one lane only and is being diverted off at junction 20 of the M25.