About 30 activists gathered near a university in southwestern Moscow to protest discrimination against gays and lesbians in Russia. The group, which included British gay rights advocate Peter Tatchell, waved flags and chanted slogans, including: "Homophobia is a disgrace of this country!" and "We are demanding equal rights!"
About a minute after the protest began, riot police charged into the group and began to grab demonstrators, dragging them to waiting buses. Tatchell was talking with reporters when police hauled him away.
"This shows the Russian people are not free," he said.
Moscow is hosting the Eurovision song contest finals later Saturday. Europe's most prestigious pop music contest has drawn attention to gay rights in Russia, with some singers threatening to boycott the event if the gay pride parade was not allowed to happen.
Russian gay rights movement leader Nikolai Alexeyev was among those detained Saturday.
After the protest was over, riot police seized other gay activists who started to speak with reporters. Police ripped the shirt and bra off one woman, who identified herself as Ksenia Prilebskaya, and roughly pushed her into a police bus.
Eduard Murdin, 40, a human rights activist from the Russian city of Ufa, was flanked by two officers who pinned his arms behind him and marched him, head bent over, to a waiting bus. "All we wanted was a legal protest," he said as he was led away. "But we were blocked. What else could we do?"
"Freedom of expression for homosexuals," shouted Nikolai Bayev, 34, a gay rights activist from Moscow, as police took him away. Among those detained was Andy Thayer of Chicago, co-founder of the Gay Liberation Network.