Protesters occupying the Puerta del Sol square in Madrid to demonstrate against Spain's economic crisis.(AFP photo)
Everything was done peacefully and there were no injuries and no arrests, a police spokeswoman said.
She said the operation began at around 6am (0400GMT) in Madrid's Puerta del Sol square and along the Paseo del Prado avenue, and both sites were cleared of all traces of the encampments three hours later.
The "indignant" movement, also known as the 15-M after the May 15 launch date, emerged after thousands of protesters set up camp in the Puerta del Sol ahead of municipal elections to protest the misery the economic crisis has inflicted on ordinary people.
The vast ramshackle protest 'village' was dismantled on June 12 but the group has since mounted a series of protests, rallying an estimated 200,000 people across Spain on June 19.
The protesters have won broad public support in their fight against austerity measures, soaring unemployment and corruption-tainted politicians.
"Wake up, you've got five seconds to pick up everything and leave," the police told the campers on Tuesday, according to Spain's leading daily El Pais.
A statement from the organisers said about 20 police vans entered the Puerta del Sol to evacuate the square, where "22-23 people had spent the night."
It said the operation was peaceful.
"The aim was to evacuate (the square) and leave no trace of the information point that has been serving all those interested in the movement since the 15-M camp was taken down."
The information point, InfoSol, "is one of the symbols of civil movement that emerged" from the Puerta del Sol camp.
"Information is a right of all people, and this was exemplified in InfoSol, which told people how they could participate in the global consciousness that has arisen with the 15-M movement."
Some of the protesters told Spanish media they believed the police operation was linked to the visit of Pope Benedict for the World Youth Day festival in Madrid August 16-21.
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