A largely peaceful demonstration against global capitalism flared into violence yesterday when anarchist protesters attacked a McDonald's restaurant and fought a running battle with riot police during clashes across the centre of London.

In echoes of the riot that caused havoc in the City last June, demonstrators selected the international burger chain, apparently as a token of their contempt for capitalism.

The attack, in which furniture was wrecked and windows smashed, marked the start of sporadic clashes that marred an otherwise peaceful day of protests by about 5,000 people who marched through London, congregating in Parliament Square, where they planted flowers and dug an impromptu "pond".