Detectives have identified a linked series of attacks on women on the Southwark and Lambeth border and are appealing for further victims to come forward.
"A male suspect has been identified and is currently in custody," said a Metropolitan Police spokesman.
"Despite this arrest, officers believe there could be more victims in the area and are asking them to contact police.
"The area in question is bordered by Blackfriars Road, Stamford Street and Waterloo Road.
"Any victims are asked to call detectives on 020 8649 2196."
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