Farringdon Road was brought to a standstill after an operation by armed police at around lunch time today.
Several police vehicles were involved in stopping a vehicle on the road in east London and three men have been arrested in the pre-planned operation.
The incident is not terror related, the Metropolitan Police have said.
The road, which runs from near Kings Cross towards Blackfriars was closed from 12pm when police officers swooped.
Traffic was halted briefly between Clerkenwell Road and Ray Street Bridge and public transport diverted. Traffic is now moving again.
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