The Met stated officers had been referred to as at 5.23am following an incident close to St George’s Method.
A 25-year-old lady was taken to hospital for evaluation and is being supported by specialist officers.
A 31-year-old man has since been arrested on suspicion of rape and theft, and stays in custody.
Anybody with info ought to name the police on 101 with the reference 1448/25SEP.
Data will also be supplied to Crimestoppers, anonymously, on 0800 555 111.