About 400 leftists rampaged through a working class section of Berlin, smashing windows, erecting barricades and pelting police with rocks, officials said Monday. Police said 134 people were arrested and 53 police officers injured in the violence in West Berlin's Kreuzberg district. But the city policemen's union said that 87 officers had been injured. City officials said the violence late Sunday and early Monday was a sign of what officials could expect in September, when finance chiefs gather in West Berlin for a World Bank meeting. ``This was just a trial run for the World Bank meeting,'' city interior affairs chief Wilhelm Kewenig said. Some stores were looted after the windows were smashed, a police statement said. Police said one group of hooded men broke into an apartment and roughed up a 21-year-old man who had been photographing the melee. The vandalism started after an estimated 8,000 people marched in a May Day parade in the working class neighborhood of Kreuzberg. Young leftists in the Kreuzberg district, an area of high unemployment, stage protests nearly every year on May Day. Demonstrations are anticipated during the World Bank meeting here. Leftists maintain Western bankers should forgive the debts of heavily indebted developing nations.