About 100 protesters walked the streets of central London on Tuesday (June 11) under the watch of police to demonstrate against the G8 summit, due to be held in Northern Ireland next week.

More protesters gathered outside oil company BP's headquarters, while others chanted "war criminals" at the office of U.S. defence company Lockheed Martin Corp.

After scuffles and arrests earlier, the afternoon's scattered marches were largely peaceful, with protesters banging drums and dancing.

Some were against the idea of the world's richest leaders meeting to decide global policy.

"I don't think the world's most powerful countries should be getting together and forming agendas in this way. It's very undemocratic, it's based on the fact that they have the most money and the most weapons, essentially. It shouldn't be based on that, it should be based on a much more open and equal process where the world gets to negotiate things," said Mark Weaver, an activist with the Occupy movement.

Last month, Stop G8 issued a map of 100 potential targets for people to "show their anger", identifying offices of financial organisations such as banks, hedge funds, defence manufacturer BAE Systems and mining and energy companies including Arcelor Mittal and BP.

The list includes hedge funds Man Group and Paulson, private equity firm Blackstone, banks such as Citi and Barclays and embassies including those of Saudi Arabia and the United States.

The group, which describes itself as an anti-capitalist network "made up of autonomous groups and individuals", had refused to cooperate with police.

Presented by Adam Justice