Soon a bus with OMON riot police and people from "Center of Counteraction Against Extremism" CPE came to disperse crowd, which was gathering peacefully and had not intentions to demonstrate at the spot.
According to texts posted to some blogs, aroup of people moved to metro, police tried to grab people but everyone was succesfully dearrested.
Later in the evening part of the people who gathered took metro to office of pro-Kremlin youth organisation "Young Russia" (Rossiya Molodaya), which is openly cooperating with organisation "Russkiy Obraz" (Russian Way), linked to suspected murderers of lawyer Stanislav Markelov and anarchist journalist Anastasia Baburova. Office of "Young Russia" was attacked with rocks, stones, flares and road signs. After attack, anti-fascists escaped.
According to anonymous statement posted to some indymedia sites (for example here: http://piter.indymedia.org/node/8659), "Young Russia" was picked as a target due to its links to neonazis.
More on Young Russia Nazi connection:
More on Ivan Khutorskoy: