Update: The motorway is now open in both directions at j18.

The M25 was shut in both directions after a lorry crashed into the central reservation.

The incident has happened at j18 for Chorleywood and an air ambulance has been called to the scene and is set to land on the motorway. Police were called at 4.27pm.

By 7.30pn the clockwise carriageway at J18 had two of its lanes reopen past the scene of the collision.

On the opposite carriageway, the anti-clockwise remained fully closed at J18, causing a seven mile tail-back.

Traffic was being being diverted via the adjacent slip-roads. 

Watford Observer:

Watford Observer:

The crashed lorry has also shed its load, which appears to be sanitary products.

At the moment, traffic does not appear to be able to get onto the motorway at j18.

Watford Observer:

Local routes are already very badly affected including the A404 between Chorleywood and Rickmansworth, the country lanes towards Sarratt and Chandlers Cross, and all roads west of Rickmansworth towards Rickmansworth town centre.

Traffic is also heavy in both directions on the A41 between Hunton Bridge and the M25 at j20 and delays can be expected at j21 for the M1 as well as on the A405.