A few dozen activists had gathered at Palace Square in defiance of a ban.
August 4 in Saint Petersburg, Russian police arrested more than 25 human rights defenders of lesbian, gay, bisexual, and transgender (LGBT) persons participating in an unauthorized rally, reports the Chronicle.info with reference to Radio Liberty.
Police detained campaigners who unfurled rainbow flags or held placards and dragged them into a police bus.
The city had officially denied the request of the LGBT activists to hold a rally so the protestors each demonstrated alone within the square in a bid to avoid the event being called a gathering.
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Three policemen were seen carrying one man who looked despondent but still held his multicoloured banner aloft above his head.
There were no clashes between Russian police and the activists, but those holding up protest materials were pulled into a police van against their will.
The protests were part of pride celebrations around the world this weekend, most notably in Brighton where around 300,000 people attended.
In 2013 Russian Federation passed laws outlawing propaganda relating to homosexuality.