Six people were injured in the accident which occurred on the London-bound carriageway of the M4 near Slough, Berkshire on Friday afternoon.

A woman who suffered head injuries was airlifted to JR2 Hospital, Oxford where her condition remains "serious".

A 51-year-old man from Peterborough, Cambridgeshire, has been released on bail until 26 April.

The accident blocked the motorway for more than five hours.

Thames Valley Police are appealing to anyone with information about the crash, which occurred at about 1220 GMT, to contact them.