Police moved in shortly after midnight to clear the campsite pitched on the plaza outside one of the city's best-known landmarks. Many campers left peacefully, but a few resisted, crying, "Shame on you!" to the officers.
Some protesters were forcibly moved by police while praying on the church steps. Police said they had arrested 23 people by 9 a.m.
The group, modeled after the Occupy Wall Street movement, last week lost a final appeal in Britain's High Court against their eviction by the owners of the site, the City of London Corp. After Tuesday's eviction, the corporation announced that the site had been cleared and was ready for cleaning.
"It is regrettable that it had to come to the need for removal but the High Court judgment speaks for itself. The site has now been cleared and the area is undergoing a deep clean," Stuart Fraser, City of London policy chairman, said in a statement.
Police also removed an Occupy London group from an abandoned school in East London. By then, several protesters had already moved to a third Occupy London protest camp in Finsbury Square in the heart of the financial district.
Others plan to regroup and decide their next move Tuesday evening at a meeting on the steps of St. Paul's, said Ronan McNern, a spokesman for the movement.
"They may have got rid of the tents, but they haven't got rid of us," he said in a telephone interview. "We are going to be visiting some old sites, and this time we mean business."
-- Janet Stobart
Photo: Authorities clear the Occupy London campsite outside St. Paul's Cathedral early Tuesday. Credit: Lewis Whyld / Associated Press