A cyclist was killed in a collision with a skip lorry at the junction of Tanner Street, Tooley Street and Jamaica Road on Tuesday lunchtime.
A Metropolitan Police spokeswoman said that officers were called to the scene, close to Dockhead, just after 1.20pm.
The male cyclist, believed to be aged 20, was pronounced dead at the scene. He has not yet been formally identified.
Anyone who witnessed the collision, or who saw the lorry shortly before the collision, should call police on 020 8285 1574 or, to remain anonymous, call Crimestoppers on 0800 555 111.
Scotland Yard has confirmed that a man in his 40s was arrested on suspicious of causing death by careless driving. He remains in custody at a south London police station.
Traffic was diverted via Abbey Street. Buses on route 47, 188 and 381 were diverted via Southwark Park Road and Grange Road.
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