HONG KONG — A group of pro-democracy activists from Hong Kong were prevented Saturday from boarding a flight to Beijing, where they had hoped to lobby the Chinese government to heed their calls for free elections.

The plan by the three activists, leaders of the Hong Kong Federation of Students, to talk directly with Prime Minister Li Keqiang and other officials had been certain to be rejected by the Chinese government. But the attempt to fly to Beijing represented another round in a battle of images and rhetoric that has pitted the protesters against the Hong Kong government and Beijing.

Image Alex Chow after he and two other student leaders were prevented from boarding a flight to Beijing. Credit... Tyrone Siu/Reuters

In the end, the three student leaders — Alex Chow, Nathan Law and Eason Chung — did not even leave Hong Kong. Cathay Pacific, the airline whose subsidiary, Dragonair, operates the flight to Beijing that they planned to board, told them that the Chinese authorities had rescinded their entry permits, which Hong Kong residents need to go to mainland China, according to Lester Shum, another student leader. Dozens of cheering and singing supporters gathered in the airport’s departure area, many holding up yellow umbrellas, which have been an emblem of the protests since demonstrators used umbrellas to ward off police pepper spray.