HONG KONG -- Leaders of student protest groups in Hong Kong, who planned to fly to Beijing and seek direct meetings with top Chinese leaders, were denied boarding for their flight on Saturday due to invalid documents.

Federation secretary general Alex Chow, and three other key student leaders of Occupy Central movement arrived at Hong Kong's international airport Saturday afternoon to leave for Beijing, but were denied boarding for their Cathay Pacific flight after being informed that their travel documents were invalid.

Their Home Return Permit, the visa which Hong Kong residents require to travel to mainland China, had been canceled, said an airline company staff.

Hong Kong's Chief Secretary for Administration Carrie Lam said on the same day that there is no need for the student leaders to take their demands to Beijing, saying that the central government in Beijing is well aware of the different opinion of some Hong Kong people and has made decisions accordingly.

President of Hong Kong's Legislative Council Tsang Yok-Sing said the objective of the Federation of Students is unclear, adding that the central government has reiterated the baseline of Hong Kong's constitutional reform for many times, and there is no space to talk outside the baseline.

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