A woman in her 70s has died and four others have been seriously injured after a car smashed through the window of a Costa Coffee shop today.

The woman was sitting with her family in the window of the shop in Market Square, Westerham, when the tragedy happened.

All emergency services - including the air ambulance - were called just after 10.30am, after an Audi, driven by an 88-year-old man, crashed into several cars before ploughing into the side window of the cafe.

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Witnesses told KentOnline that the driver appeared to have collapsed at the wheel just prior to the accident.

Kent Fire and Rescue said firefighters had cut two people from the car.

The Audi was removed from the shop at about 6.20pm.

VIDEO: Tragedy at Costa

An ambulance spokesman said more than a dozen ambulances attended, including Critical Care Paramedics and a Hazardous Area Response Team.

She said: "Medics treated six patients in total, including one patient who died at the scene.

"Five further patients were treated and then taken to hospital.

VIDEO: One dead and four injured in Costa Coffee crash

"Two patients, a man and a woman, were taken by ambulance to St George's Hospital in London, both with serious injuries.

"A man and a woman were taken by ambulance to the Princess Royal Hospital in Farnborough – again both with serious injuries.

VIDEO: Interview with chief inspector Roscoe Walford

"A woman with minor injuries was also taken by ambulance to Pembury Hospital.

"Our thoughts are with all those involved in and affected by this very sad incident."

The driver of the car is thought to be one of those being treated.

A former Costa worker said on twitter she has been in touch will ex-colleagues at the cafe, and believes all are unhurt.

Police say the investigation both inside and outside the shop could take up to five hours, and the roads are expected to be closed into the evening.

Once the investigation is complete, the vehicle will be removed from the premises, according to police.

Chief Inspector Roscoe Walford told KentOnline: "A black Audi was travelling down Westerham High Street when, for reasons unknown, it hit a couple of cars, travelled along the footpath and into the window of the coffee shop where people were drinking coffee and celebrating Christmas eve.

"We will be carrying on our investigations for a good few hours.

"The family of the deceased have been informed."

A member of staff at nearby Chocs On The Green said: "It's unclear what has happened. There was a very loud bang.

"The store was very busy at the time and people were leaving at the time the car crashed. It's hard to say how many are injured."

Sally Pendleton passed the coffee shop just five minutes after the accident happened.

She told KentOnline: "There was a man still in the car - he seemed OK but a few people were hurt and in shock."

Another witness, Matt Jenner, said: "A car has driven into the side of Costa, the whole car is inside. Westerham is cut off. There are sirens everywhere."

A witness centre has been set up at The Grasshopper pub in The Green.

A police spokesman said: "Kent Police was called to reports a car had collided with a property in The Green, Westerham.

"Officers, Secamb and KFRS are at the scene and there are a several reported injuries. The road has been closed."

Costa Coffee tweeted to say they were aware of the incident.

A spokesman said "thoughts are with everyone involved."