Police were called to an incident
The M2 near the Chatham turn-off was closed this morning after a car overturned, throwing a woman passenger out of the smashed sunroof.
It is believed the driver of the Vauxhall Astra hit surface water between junction three for Chatham and junction two for Strood on the London-bound carriageway and lost control.
The woman, the man's daughter, suffered head injuries in the accident which happened at about 6.30am.
It is thought they were on the way to Heathrow Airport to catch a flight to Armenia.
Watch manger Lee Murphy from Medway fire station said the woman, in her 20s was thrown from the vehicle, landing on an embankment.
An off-duty doctor gave medical help while waiting for paramedics to arrive and take her to hospital. He said she remained conscious throughout.
All four lanes remain closed and are expected to re-open later this morning. Police are advising people to avoid the area.