Four people were injured and traffic brought to a standstill following a multi-vehicle collision on the M25 near Leatherhead this morning (January 31).

Surrey Police reported that two cars and a heavy goods vehicle were involved in the incident, which occurred near Junction 9 near Leatherhead at around 6am Thursday morning.

Long delays hit the morning rush hour between Junctions 9 and 10 following the collision, with British Transport Police forced to divert traffic via the nearby Cobham services.

Surrey Police revealed in a statement posted at 8.34am that they were conducting investigations into the incident and appealed for witnesses (see below).

Surrey Police said: "We are appealing for witnesses following a serious collision on the M25 this morning near to Cobham Services. The collision, involving a silver Mazda, a black Volkswagen Golf and a white heavy goods vehicle, happened at around 5.51am. The anticlockwise carriageway is currently closed while officers carry out their investigations. Motorists are advised to find alternative routes. Diversion information is available here: http://surreybe.at/7394d"

It was revealed that two people who had been in the Mazda at the time of the collision suffered serious injuries, while the couple in the other car sustained minor injuries.

Surrey Police said: "A woman in her 60s and man in his 70s in the Mazda have suffered serious injuries, while a man and woman in the VW Golf have been taken to hospital with minor injuries. The driver of the HGV, a man was uninjured.

"Anyone with any information, or dashcam footage should contact Surrey Police via 101 or use http://surrey.police.uk/TellUsMore, quoting reference PR/P19024109."

In a later update posted at 9.49am, the Surrey Police Twitter account reported that a single lane between Junctions 9 and 10 had reopened.

The tweet read: "1 lane is now open on #M25 A/C J10-9 at #Cobham. Remaining lanes likely to be closed for 2-3 hours while roadside investigations continue."