SUPPORTERS of leading dissident Han Dongfan yesterday called on senior party leader Qiao Shi to press authorities to admit it was a mistake to revoke Mr Han's passport. More than 50 people demonstrated outside the Xinhua (New China News Agency) headquarters against Beijing's decision to cancel Mr Han's passport, while some prominent pro-China figures cast doubts on the legality of the cancellation order. Chanting slogans such as ''Chinese nationals have the right to return to China'', they urged the National People's Committee chaired by Mr Qiao to immediately convene a meeting to study whether the decision of the executive authorities had violated the Chinese Constitution and international law. The rally was organised by the Hong Kong Alliance in Support of the Patriotic Democratic Movement in China, which has been labelled subversive by Beijing. In an open letter to Mr Qiao, who is also a Politburo Standing Committee member, the alliance said Mr Han's case indicated that some officials in the Chinese Government had abused their powers, blatantly defied laws and acted wantonly. ''Chinese people all over the world were shocked and felt humiliated,'' it said. Mr Han was told by Xinhua officials on Saturday that his passport had been declared void because he ''has done something opposing the Government and undermining the interests of the country''. The alliance said in its letter: ''Only the judicial authorities have the power to determine whether any activities of individuals are against the Government in a society with rule of law.'' The alliance said Mr Han has only voiced workers' concerns about free movement at international conferences. ''This is in conformity with the Chinese Constitution which allows freedom of speech. Even his decision to return to China to organise trade unions is lawful,'' the letter said. A close adviser to the Chinese Government, Xu Simin, who had sent a letter to Executive Vice-Premier Zhu Rongji on Mr Han's behalf, said he received a similar reply to the one given to Mr Han by Xinhua. Mr Xu, a Standing Committee member of the Chinese People's Political Consultative Conference, said he would seek legal advice on whether Beijing's decision was unconstitutional or violated international law. ''I have no idea if the decision to revoke his passport also means his nationality has been revoked.'' A Hong Kong Affairs Adviser, Tsang Yok-sing, said he would discuss with other local members of the National People's Congress and the Chinese People's Political Consultative Conference how to relay the feelings of Hong Kong people about Mr Han's case andwhat they could do to help him. Wang Dan, a student leader of the 1989 democracy movement who spent four years in jail, said in Beijing he had decided not to leave the country. after learning of Mr Han's plight.