Hundreds of people were evacuated from Canada Square after reports of a possible fire on Monday morning.
Firefighters were called to reports of a burning smell at the Bank Of America building in Canary Wharf at 10.30am on Monday, July 10.
A spokeswoman for the London Fire Brigade confirmed there had not been a fire, and said: "Two light fittings were showing a high temperature on the third floor. We isolated the power source.
"Approximately 300 people self evacuated before the arrival of the brigade."
Four fire trucks were parked outside the bank while the fire service worked to establish where the burning smell has come from. Employees were allowed back into the building shortly before midday.
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