Police in St. Petersburg have detained at least 24 people after a sanctioned demonstration against "crime involving foreign migrants" in a downtown area sparked violence on the city's main street and in a market area, local media reported.
At least 150 people took part in the march on Sunday afternoon at Mars Field, city police said. A correspondent for the local Fontanka.ru news website estimated the number involved at around 300-400.
"Eight people were held for public order offenses," the police said, mainly for lighting flares.
Speakers at the meeting issued a proclamation condemning the city governor and the local chief of police, and called for the release of a nationalist figure, Nikolai Bondarik, who was arrested recently on suspicion of attacking people of non-Slavic appearance.
Following the end of the meeting at around 4:40 p.m. local time, around 50 people, shouting slogans, headed for the city's Nevsky Prospekt, attacking bystanders who appeared to be non-Russian. The group was broken up by riot police.
Trouble also broke out at around the same time at the city's Apraksin Dvor market area, witnesses said. Youths threw stones and smoke bombs at market stall holders, many of whom are migrants. Some of the market workers responded to the attack by using non-lethal firearms.
Riot police detained 16 people at the scene, the police said. Witnesses said some of those participating in the attack on Apraksin Dvor had attended the Mars Field demonstration.
The trouble comes just a week after Moscow experienced its worst civil unrest in years, when rioters attacked a market area frequented by migrant workers after a local man was knifed to death by a man police later said was thought to be non-Russian.