BERLIN, NOV. 13 -- The Mainzerstrasse kids today reinforced their barricades, nursed their wounds, and prepared for further battle.

For five hours early this morning, a few hundred anarchist apartment squatters on this dark, decrepit street in eastern Berlin fought 1,400 police officers. The squatters set fires and pelted police from the rooftops with paving stones, molotov cocktails and metal rods. Police fought back with tear gas and water cannons.

When the gas cleared, 20 squatters had been arrested and 135 police officers injured, six of them seriously. The barricades stood, the police retreated and the squatters returned proudly to their communal apartments.

Today, they wore their scrapes and scratches like badges of honor. They dug foxholes across the cobblestone streets. They piled floorboards atop the 30-foot-thick barricades they have erected to fend off police assigned to evict them from apartment buildings they have declared their own.

At a corner where the squatters' turf ends and working-class Berlin resumes, an old man yelled tonight: "You are all children, dumb, primitive children. You should act with good, quiet words, not with stones and fire."

"I'm not a child," a squatter yelled back. "I'm 19. In the Nazi time, we saw how conscientious and obedient the adults were. We're not obeying anyone."

The graffiti on the outside of the buildings on Mainzerstrasse says "Learn to burn," "Arm yourselves!" and "Where the state stops, life begins."

In preunification West Berlin, stylized, virtually choreographed battles between anarchists and police were an almost weekly ritual. But since the fall of the Berlin Wall, hundreds of West Germans have moved into 130 empty apartment buildings around what was East Berlin, spreading their confrontational methods to a city in which open conflict with the authorities was unknown.

Berlin, like most German cities, suffers from a housing shortage and a surplus of students. Many German university students stay in school for a decade or more, taking advantage of generous state subsidies and waiting for places in the tight job market.

The combination has made squatting a problem in many large German cities, but in Berlin, there was an added factor: Because West Berliners were exempt from West Germany's mandatory military service, the city became a magnet for draft-dodgers and anarchists.

These students have turned occupying abandoned buildings into a political statement. They have organized bookshops, information cafes, demonstrations, food co-ops, and communal apartments.

For six months, their presence in buildings that previously belonged to East Germany's Communist government went largely unchallenged. The squatters were mostly West Germans looking for free housing, joined by a few East Germans fearful of the stiff rent increases planned for January.

This week, police decided to end the occupation. "It's an extremely complicated question because there are still property ownership questions to be cleared up," said Erich Paetzold, the member of the city government in charge of police matters. He defended the police action as necessary to regain control over whole blocks of the city that have been taken over by squatters.

But the Berlin police union criticized the city action. "Some 135 injured police officers and untold plunder and destruction are the result of a flawed security policy by the Berlin police," union chief Martin Gregg said.

The violence may not be over. Caravans of police reinforcements were on their way to Berlin from western Germany today, and squatter leaders said they expected another battle later this week.

Street violence, virtually unheard of during 40 years of Communist control of East Germany, has spread throughout the country in recent weeks. Neo-Nazi groups have held anti-foreigner marches. Anarchists who portray themselves as anti-fascists have attacked police.

Police in Leipzig last week killed one person and wounded three others after neo-Nazis and soccer hooligans went on a rampage through city streets. As a result, the country's soccer officials today canceled a planned Nov. 21 match pitting the world-champion West German squad against all-stars from the former East German team.

"When young people in Germany try to use other means to point to problems, no one listens," Prof. Wilhelm Heitmeyer said on German television today. "Politicians should not miss the warning signals."

On Mainzerstrasse, where squatters sat around a giant bonfire in the center of the street tonight, the talk was of holding on for as long as possible.

"When the owners of buildings let apartments go to ruin so that they can build offices or expensive apartments later, then we have the right to stay here," said a 20-year-old squatter from Bavaria who refused to give his name. "We want to live with people who think the same as us. We put a lot of work into these buildings."

Most of the squatter community do not work but support themselves with student grants and perhaps sales of T-shirts at the squatters' souvenir stand. They are a bedraggled bunch, dressed mostly in black, their hair painted in bright streaks of color, their noses and ears pierced by multiple rings.

Many of the squatters call themselves Communists and speak of the fall of the Berlin Wall as "the moment all hopes were buried," as Martin, a spokesman for the group, said.

"We would like to see free housing for all," said the sociology student at the Free University in western Berlin. "We came over to the East in search of a utopia. We wanted a communism that was not dogmatic or Leninist, but a sense of freedom to develop opinions for the common good."

That, Martin admitted, will not happen now that the two Germanys are one. But the squatters hope nonetheless to maintain their own low-cost community. Talks with city officials have broken down.