London Bridge, the railway station and nearby streets were sealed off on Tuesday afternoon while police investigated a suspicious vehicle.
The evacuation began at about 2.15pm and cordons were lifted soon after 3.35pm.
Rail services were halted and buses were turned round at Elephant & Castle.
Southwark Police said that the incident was "found to be not suspicious".
Southeastern warned rail passengers to expect delays for the rest of the day.
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