Spanish police fired rubber bullets and swung truncheons to disperse anti-crisis protesters in a Barcelona square Friday as cleaning crews cleared their tent camp.
Catalan police in anti-riot gear moved in after about 50 protesters sat down on the street to block a convoy of cleaning trucks leaving the Plaza de Cataluna square with remnants of the encampment.
Police, some with plastic shields, were shown on television dragging protesters along the street and swiping with truncheons at activists, who had been chanting: "They shall not pass."
An AFP reporter at the scene saw rubber bullets fired.
The protest blockade was broken up within minutes but about 100 protesters regrouped in the square. They were surrounded by two police cordons blocking hundreds more people from entering from nearby roads.
Demonstrators chanted: "The people, united, will never be defeated!" and "No to violence!"
Cleaning crews with 10 lorries dismantled the last of the tents under police surveillance. Later, police left the square and let thousands of demonstrators flood in but by mid-afternoon only a few hundred remained.
Ten people were taken to hospital, mostly for multiple bruises and psychological shock, after the clashes, said a Catalan emergency medical services spokeswoman.
A total 87 people including one police officer were treated, mostly for light injuries, she said.
"Their cleaning has washed up blood, people bleeding from the head," said a comment on the Barcelona protest's Twitter account "acampadabcn".
It was the first attempt by police to clear demonstrators from a nationwide movement that began May 15 and grew in city squares across the country.
Police said they had to clear the encampment in case Barcelona beat Manchester United in the Champions League football finals in Wembley on Saturday and the square was needed for celebrations.
They also swooped on an encampment in Lleida, in the same northeastern Spanish region of Catalonia, where the Plaza Ricard Vinyes was cleared for possible football celebrations.
"Once the cleaning is finished they can go back but without the tents, knives and potentially dangerous objects," a police spokeswoman said in Barcelona.
Activists vowed to return.
"They are making us leave because of the match but we will come back again here or elsewhere because our match is more important," said Albert Bonet, a 42-year-old artist who was in the protest.
The demonstrators are known variously as "the indignant", "M-15" after the birth date of their movement, and "Spanish Revolution".
Mostly young, they have gathered in city squares across Spain in peaceful protests to decry mainstream political parties, soaring unemployment, corruption and welfare cuts.
At the vanguard of the rallies in Madrid, protesters remained camped in the central square Puerta del Sol but in smaller numbers than at the peak just before Spain's May 22 general elections.
In the municipal and regional polls, voters punished the ruling Socialist Party for the grim economy and handed a huge victory to the conservative opposition Popular Party.
Madrid protesters say they plan to decide Sunday how to carry on the movement.