SEOUL: As riot police fired tear gas canisters, 3,000 protesters in downtown Seoul hurled chunks of concrete ripped from sidewalks and beat police with pipes, shouting "No to the evil law!" Similar clashes involving thousands of marchers occurred in Anyang city, near Seoul, and in Daejon, south of the capital, where seven workers were hospitalized after being clubbed by police, and eight others were detained for questioning. The government is coupling the crackdown on the streets with one in the courts, deciding Thursday to pursue arrest warrants for union leaders. Judge Lee Sang-chul ordered seven leaders of the outlawed Confederation of Trade Unions to appear in court by Friday morning, and other district courts issued subpoenas for 13 others, including six Hyundai union leaders in the southern city of Ulsan. In overnight raids Thursday, police raided the empty head offices of the outlawed Confederation of Trade Unions and its three subsidiary groups, seizing hundreds of documents and anti-government materials as evidence of their illegal activity, officials said. Confederation leaders plan more demonstrations Saturday, but continue to scale back the strikes in an effort to encourage government compromise. In addition to Hyundai Motors Co., whose workers will work up to ten hours a day, three other car makers will resume partial operations until Tuesday, when the unions have threatened an all-out strike if the labor law is not rescinded.