AN investigation has been launched after a taxi driver was seriously injured in a motorway pile-up.

The 59-year-old man was in a collision on the M25 near to junction 25 with Enfield on Thursday, December 16.

His silver Hackney cab collided with a silver Vauxhall Vectra, but as the two drivers inspected the damage, a grey Audi A6 also crashed into the two cars and the man was seriously injured.

Police closed the clockwise section of the motorway for several hours after the crash, at around 6.30am, as the man was rushed to hospital where he remains in a critical condition.

Officers from the Collision Investigation Unit at Chadwell Heath have appealed for witnesses to the crashes to call 0208 597 4874 with information.