HONG KONG—One of Hong Kong’s most established pro-democracy civic organizations said it is letting go its paid staff and halving the size of its steering committee after Beijing stepped up its suppression on opposition activity in the semi-autonomous Chinese city. The Hong Kong Alliance in Support of Patriotic Democratic Movements of China is best known for organizing an annual rally and candlelight vigil remembering those killed in the bloody 1989 suppression on pro-democracy protests in Beijing’s Tiananmen Square. The group said in a statement Saturday that seven of its 14 remaining steering committee members had decided to step down in the face of “growing political and legal risks.” Of the seven members remaining, three are currently in jail for protest-related activities—chairman Lee Cheuk-yan as well as vice chairmen Albert Ho Chun-yan and Chow Hang-tung. Letting go of staff was to “ensure their safety” and would take effect at the end …