One of the main gathering points for participants in the May Day protests was in Great Suffolk Street, SE1
It is thought that police helicopter activity in the area last weekend was in connection with this location.
Anti-capitalists also congregated at the Elephant and Castle, which was the focal point of the South London May Day Collective's demonstration.
Later police closed Westminster and Lambeth bridges to prevent the anarchists from joining the larger crowds in the West End.
The Old Kent Road was expected to be a target, but the trouble didn't materialise.
Two protesters were arrested in Southwark during the morning on suspicion of being in possession of drugs.