Emergency call handlers received reports just before 6pm on Friday 9 August 2024, of a three-vehicle collision close to junction five on the M20 coast-bound.
Officers attended the scene alongside South East Coast Ambulance Service, where a woman in her 30s was flown to a London hospital for treatment to serious injuries.
A 35-year-old man from Tonbridge was arrested in connection with the incident and has since been released on bail until 10 November, while an investigation is underway.
Anyone who witnessed the incident, but has not yet spoken to police, is urged to call 01622 604 100, quoting reference 09-1149.
Motorists with dashcam and residents with private CCTV are also asked to check for relevant footage.