
LONDON — Thousands of people marched through London on Saturday to demand punishment for bankers, power to the poor and protection of the environment at a protest meant as a wake-up call to world leaders gathering here this week for an economic summit.
It was one of the largest demonstrations this city has seen since massive rallies against the invasion of Iraq six years ago. The turnout, estimated at about 15,000, reflected the depth of popular anger over Britain’s economic crash and the perceived greed of bankers and other high-fliers whom many people blame for it.
Beneath a sea of banners, marchers from trade unions, charities, environmental groups and churches snaked through the streets to converge on London’s Hyde Park. Placards called for “people before profits” and “jobs, not bombs,” in a nation suffering its worst unemployment in more than a decade.
“It’s people that make changes, not governments,” said Gail Cartmail, assistant general secretary of Unite, one of Britain’s biggest unions. “There should be more investment in public services and housing, not less, (and) greater help to get people back into work.”
The leaders of the Group of 20 Finance Ministers and Central Bank Governors, an organization representing the world’s biggest developed and emerging economies, will meet here Thursday to discuss ways to pull the global economy out of its hole.
In Berlin, raucous protests drew thousands of participants, and hundreds congregated in Paris.
Saturday’s protest in London offered a harbinger of demonstrations planned for this week — and of the security nightmare they present for police. Several activist organizations have scheduled events around the city Wednesday, when many of the G20 leaders are set to arrive, and some underground anarchist groups have threatened to storm buildings in the financial district.



