A man was trapped in his car for an hour with head injuries after a crash at traffic lights on Saturday morning.
The driver was taken to St George's Hospital with head injuries after the accident between two cars at the junction between Gander Green Lane and St Dunstans Hill.
The 37-year-old was cut out of his car by firemen after the smash on the road at 6.50am.
Another man was also cut out of his car and taken to St George's.
Police said one car was believed to be on its side.
Residents living nearby said the road was cordoned off for hours as fire officers laid down sand to absorb spilled petrol.
Sutton’s fire brigade’s blue watch station manager Richard Young said: “There were two people trapped in the car.
“The officers had both men removed from their vehicles at 7.25am.
“It was a high-impact incident so sand was put down to soak up any oil.”
A London Ambulance Service spokesman said: “We got a call at about 6.50am to reports of a road traffic accident between two cars.
“We sent one single responder car, two ambulances and an air ambulance doctor in a car.
“A 37-year-old man was taken to St George's Hospital as a priority and a second man was also taken to St Georges Hospital.”
A police spokesman said: “One car was on its side.
“The road was closed until 8.30am.”
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