By Alissa de Carbonnel
MOSCOW (Reuters) - Police stepped up security in Moscow on Tuesday to prevent a repeat of rioting over the killing of an ethnic Russian as crowds of Muslims celebrated the Islamic holiday of Eid al-Adha.
Advocacy groups have warned migrants from mainly Muslim ex-Soviet states in Central Asia and the Caucasus of a risk of attacks after the worst racially charged unrest in the Russian capital in three years.
Police named a man from Azerbaijan as a suspect in the fatal stabbing of a Russian that led to rioting over the weekend.
Outside Moscow's main mosque, police set up barriers and metal detectors to control the flow of people. Ethnic tension is often higher during the Islamic holiday because crowds spill out into the streets around the city's few mosques.
Crowds of residents in southern Biryulyovo district have called for tougher policing of migrants and roamed the streets hunting for men who matched a police description of a suspect in the stabbing death last week of Yegor Shcherbakov, 25.
On Sunday, rioters smashed shop windows, clashed with police and stormed a market in Biryulyovo where many migrants work.
In an apparent move to appease residents, Moscow's police chief fired the senior police officer in the neighborhood district on Tuesday.
On Monday, police raided the market in Biryulyovo and detained more than 1,200 people to check for any wrongdoing, and about 450 migrants were detained at another site.
A Moscow police spokesman, Andrei Galiakberov, told Interfax that police had indentified the suspected killer. He named him as Orkhan Zeynalov, a citizen of the South Caucasus state of Azerbaijan, a mostly Muslim former Soviet republic.
Migrant labor has played a significant role in Russia's transformation during an oil-fuelled economic boom that took off around the time President Vladimir Putin came to power in 2000.
But many in Moscow chafe at the influx of migrants from Russia's heavily Muslim southern regions and the ex-Soviet states of the Caucasus and Central Asia. Some Russians have called on the government to impose visa requirements for people arriving from Moscow's former vassal states.
(Reporting Alissa de Carbonnel and Ian Bateson,; Editing by Steve Gutterman and Angus MacSwan)