BEIJING (Reuters) - Chinese police have freed dissident Wang Youcai after taking him in for questioning and warning him to drop a plan to register a political party, a Hong Kong-based human rights group said on Tuesday. Wang and two other dissidents in the eastern city of Hangzhou tried to register a political party to challenge communist rule last Thursday, the day U.S. President Bill Clinton arrived in China for a nine-day visit. Police summoned him for questioning on Monday and released him six hours later at around midnight, the Information Centre of Human Rights and Democratic Movement in China said. Public security officials warned Wang that they would take further action if he did not drop his plan to register the Chinese Democratic Party, the centre said. Wang told police it was none of their business and that he would try again to register the party with Zhejiang‘s provincial department of civil affairs, the group said.

The former student leader was jailed for three years for his role in student-led demonstrations for democracy that were brutally crushed by the army in Beijing on June 4, 1989. Clinton‘s visit, the first by a U.S. president since the 1989 Tiananmen Square massacre, has been clouded by a public row over the detention of several dissidents in the cities he was to visit.