A Waterloo street was cordoned off by police on Sunday night after a man was found suffering from a gunshot wound.
"At approximately 10.30pm on Sunday 16 June officers were made aware of a man suffering a gunshot wound to the leg in Royal Street, SE1," said a Metropolitan Police spokeswoman.
"The man, believed aged in his twenties, was taken to hospital for treatment; his condition is not thought to be life threatening."
Police are trying to discover where the man was shot.
Royal Street is opposite the entrance to the emergency department at St Thomas' Hospital.
The cordon also included an area around the Stangate block of flats at the end of Upper Marsh.
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