This photo shows a car number, 6548, of a Circle Line train involved in 7/7. It is a trailer car. Its matching driving motor car, out of shot to the left, will have number 5548. I suspect this is at Aldgate Junction and the train is Circle Line train 204.
This shows the damaged car 6713, another trailer car. The front, driving motor car of the train will be 5713.
The first four cars are then 5548-6548-6713-5713
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