The South East Coast Ambulance service was called to the A20 shortly after 2.30pm on November 5 with reports of the crash.
An ambulance crew was dispatched to the scene, joined by the Air Ambulance Charity Kent Surrey Sussex.
A person was located and airlifted to hospital.
Their condition has not been confirmed at this stage.
The A20 was closed on the eastbound approach following the incident, which was described by National Highways as a “serious collision”.
Kent Police conducted crash investigation work and have been contacted for a comment.
RELATED: Air ambulance lands after serious crash closes A20 causing ‘gridlock’
The South East Coast Ambulance Service said: “SECAmb was called shortly after 2.30pm yesterday (5 November) to reports of a multi vehicle RTC on the A20 at Swanley.
“Ambulance crew attended and were joined at the scene by the Air Ambulance Charity Kent Surrey Sussex.
“One patient was treated at the scene before being airlifted to hospital in London.”
