As the march approached the corssroads at Holborn protesters began scattering in every direction. Stewards attempted to control the protest but to no avail.
Police have now blocked the path down kingsway and are holding protesters until things settle down, outside Victoria House.
Protesters have begun to throw things at police and outbreaks of violence have been seen.
The main breakaway march is heading down Great Queen Street, while many continue to push on down Kingsway.