A British gay rights activist briefly disrupted the opening night of Mariinsky conductor Valery Gergiev’s season with the London Symphony Orchestra, walking on stage to lambast the artist for his support of the “tyranny” of President Vladimir Putin.

Peter Tatchell, an LGBT rights activist and head of the Peter Tatchell Foundation, addressed the audience at the Barbican in London on Thursday, moments before Gergiev was set to make his entrance.

“Valery Gergiev is a friend, ally and supporter of the Russian tyrant Vladimir Putin, whose regime is arresting peaceful protesters and opposition leaders,” Tatchell said. “I ask you to oppose tyranny and show your support for the Russian people.”

He also accused Gergiev of defending “the new homophobic law that persecutes gay Russians,” referring to a recent law that bans promotion of “non-traditional relationships” to minors, and of supporting the Russian government’s prosecution of Pussy Riot groups members, who are in prison for staging an anti-Putin performance at Moscow’s Christ the Savior Cathedral in 2012.

Gergiev was among those members of Russia’s cultural elite who publicly voiced support for Putin, the Peter Tatchell Foundation said in an emailed statement, citing a report by The Moscow Times. Others included jazz musician Igor Butman, violinist Yury Bashmet and opera star Anna Netrebko.

Tatchell said he was “manhandled off the stage” by security guards and then left the concert hall.

The disruption “was all over in two minutes,” Tatchell said in a statement, adding that he “never intended to disrupt the concert, only to make a short, symbolic statement.”

“Gergiev’s loyalty to Putin has been rewarded with personal honors and massive state grants for his pet projects,” Tatchell added. “Gergiev is a great conductor but he colludes with a tyrant and shows little concern for freedom and equality.”