MOSCOW — Russian police on Monday swept through a vegetable warehouse earlier targeted by rioters, rounding up about 1,000 migrant workers, checking their documents, and loading them onto vans to be investigated for criminal activity.
The raid came the day after demonstrators angry over the stabbing death of an ethnic Russian man broke into a covered market and descended on the warehouse where they believed the killer was working, throwing bottles and trash, smashing windows, and turning over cars. Police detained hundreds of rioters.
Men who worked at the warehouse in Biryulyovo, a working-class neighborhood on the outskirts of Moscow, were marched outside by police.
Dozens of people gathered nearby to pledge their support to the rioters, venting their anger at the migrants from the predominantly Muslim Caucasus region, whom many Russians accuse of pushing up the crime rate and taking badly needed jobs.
Tensions between ethnic Russians and natives of the Caucasus have long simmered, but standoffs are becoming more common.
Caucasus natives work at many markets and warehouses around the city, but even though they are from the same country, they are required to register in order to live in Moscow and face regular discrimination.
Andrei Galiakberov, spokesman for the Moscow police, described the roundup of some 1,200 people as part of a ‘‘preemptive raid’’ and said some detainees are being investigated for possible criminal connections. Police also said that they found a car full of cash and unlicensed arms.
There was no sign in Biryulyovo of the crushed watermelons and overturned cars from the night before.
Marina Ivanova, who runs a candy stall at the market, turned up for work despite the chaos of the day before. She had been helping customers on Sunday evening when she heard the rioters smashing glass and chanting racist slogans. Ivanova said she did not take sides, but worried that the conflict could escalate.