Italian Prime Minister Silvio Berlusconi promises to punish rioters after a peaceful mass rally against austerity in Rome descends into street battles.

Police arrest 45 people in New York's Times Square as Occupy Wall Street protesters move uptown, on a day of anti-austerity demonstrations worldwide.

An anti-capitalist protest in London's financial district enters its second day, with protesters camped outside St Paul's Cathedral.

Consumer groups are calling for a new deal from the energy industry at a summit on gas and electricity prices at Westminster.