One woman has died and another has suffered life-changing injuries following a hit-and-run incident in Hounslow yesterday morning.
The driver of a black Range Rover was arrested shortly afterwards.
Police are appealing for witnesses to come forward with any information.
Queueing traffic due to earlier accident on M25 anticlockwise at J23 A1(M) / A1081 St Albans Road / A1 Barnet By-Pass South Mimms, congestion on M25 to J25 A10 (Enfield).
Transport for London (TfL) last night embarked on the final stage of works to ensure the Olympic Route Network (ORN) in London is ready to begin operation on Wednesday (25 July) – just two days before the London 2012 Opening Ceremony.
The ORN is designed to ensure that all athletes, officials and the world’s media to their events on time.With just one week to go until the Games begin, final preparatory works to build the ORN took place at Westminster Bridge last night.
Over four nights, around 2,000 contractors will continue to install barriers and simplify over 120 junctions along the ORN across London.
Mayor Boris Johnson said: "The ORN is a requirement of all Host Cities and is vital in ensuring athletes, officials and the world’s media get to their events on time.... we’re working hard to introduce changes to the road network as late as possible, to minimise the impact on Londoners."
As the Olympics approaches, Transport for London is warning drivers to expect major changes to the road network from Monday.
Over the weekend, workmen will be installing temporary barriers across Central London and putting in three temporary pedestrian footbridges at Hyde Park Corner.
The official Games Lanes will not be activated until Wednesday but TfL is warning that "by Monday morning, London's road network will look and feel different". Drivers are advised to go to the official website to plan their route.