London riots: Scale of violence 'unprecedented'

Rioting has spread across London on a third night of violence, with unrest flaring up in other English cities.

An extra 1,700 police officers were deployed in London, where shops were looted and buildings were set alight.

Birmingham, Liverpool, Nottingham and Bristol also saw violence.

Speaking to BBC Breakfast, Deputy Assistant Commissioner Stephen Kavanagh said the Metropolitan police was "stretched beyond belief in a way that it has never experienced before".