The Met is responsible for Greater London (where all the riots seem to be so far). The City of London Police is responsible for the Square Mile (the actual City

The Met is responsible for Greater London (where all the riots seem to be so far). The City of London Police is responsible for the Square Mile (the actual City) in the centre. The City of London police don't especially carry firearms. That said, you may see more of the specially armed police in the City, simply because of a high terrorist threat