Police in Moscow have detained about 30 anti-Kremlin protesters outside the gates to Red Square. Opposition activists called for supporters to walk around the square on Sunday wearing the white ribbons that have become a symbol of the protest movement against Prime Minister Vladimir Putin. When police took the unusual step of closing the vast cobblestone square near the Kremlin, about 300 protesters gathered instead outside the gates. Holding hands to form a circle, they chanted \"This is our city,\" \'\'Russia will be free\" and \"Russia without Putin.\" Some of the protesters then demanded to be allowed onto Red Square and police rounded them up, leading or carrying them onto waiting buses. Putin will begin serving a third presidential term in May.