MOSCOW (AP) — Two members of the Russian feminist punk band Pussy Riot were detained Monday after a protest outside the prison colony where a Ukrainian filmmaker is being held.

Two members of the Pussy Riot band on Sunday staged a protest outside the prison colony in Siberia's Yakutia where Oleg Sentsov is serving his sentence, and put a banner on a nearby bridge reading "Free Sentsov!"

Maria Alyokhina tweeted that she and Olga Borisova were detained early Monday. Mediazona, the website focusing on court and legal news that Alyokhina and another band member helped set up, released a video showing a police squad stop the car in which the two women were traveling and take them to the police station.

Sentsov, who comes from the Crimean peninsula that Russia annexed from Ukraine in 2014, was convicted of conspiracy to commit terror attacks by a Russian military court in 2015 and sentenced to 20 years in prison. Charges against him were largely seen as politically motivated, and numerous art figures in Russia and abroad have advocated for his release.

Pussy Riot is a loose collective, most members of which are anonymous. The balaclava-clad women rose to prominence in 2012 with their daring outdoor performances aimed against President Vladimir Putin and the ruling elite. But it was an impromptu "punk prayer" at Moscow's main Cathedral of Christ the Savior, decrying close ties between the Russian Orthodox Church and the Kremlin, that got them into trouble. Three band members were convicted of "hooliganism motivated by religious hatred" for that stunt, and two of them including Alyokhina were sentenced to two years in prison.