Traffic around the area became deadlocked after the bridge was closed to vehicles for several hours during the afternoon and evening.
“The bridge experienced technical issues this afternoon and was locked in a raised position for a period of time,” Tower Bridge said on its Twitter feed.
Built between 1886 and 1894, the bridge lifts around 800 times a year and on Saturday was scheduled to be raised for the historic charter boat Sailing Barge Will.
Police announced its closure around 5:00pm (1600 GMT). It reopened to pedestrians more than an hour later, but remained shut to vehicles for several hours.
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