The demonstration on July 30, organized by the civic group Democracy, called on Western countries to continue promoting human rights in Kyrgyzstan.
Police confiscated banners and flags from participants and detained protest leader Tursun Islam, who was released later the same day.
Islam's son, Alisher, told RFE/RL's Kyrgyz Service that he was also jailed and spent three days in custody.
The human-rights bodies said the incident follows other cases in Kyrgyzstan in which human rights defenders have been "subject to pressure and the threat of criminal prosecution." They called on the Kyrgyz authorities to ensure that legitimate and peaceful protests can take place freely and without repercussions for the participants.
Turmoil In Kyrgyzstan
TAKING TO THE STREETS. Edil Baisalov, president of the largest grassroots network in Kyrgyzstan, discussed the political turmoil in Kyrgyzstan at an RFE/RL briefing in Washington. He addressed the question of whether the unrest is a healthy democratic process or a bid to derail the country's fragile democratic transition.
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Listen to the entire briefing (about 70 minutes):
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