Report: 276 Held in Moscow Over Stabbing Protest Moscow police on Tuesday detained 276 people who were protesting the stabbing death of an ethnic Russian man, a state news agency reported, while authorities said a suspect in the slaying had been arrested. The killing has raised tensions between ethnic Russians and natives of the predominantly Muslim Caucasus region, many of whom have migrated to major Russian cities for work. The suspect in the slaying is from the Caucuses nation of Azerbaijan, authorities said. The protesters had gathered Tuesday evening outside a metro station near Biryulyovo, the working-class district on the southern outskirts of the Russian capital where the stabbing occurred. Around a third of the people arrested were under 18, Deputy Director for Public Order Oleg Sigunov told the state RIA Novosti news agency. On Sunday, ethnic Russians rioted over the stabbing death, attacking buildings in the area and prompting hundreds to be temporarily detained. Russian authorities on Monday rounded up more than 1,000 migrant workers - many of them from the Caucasus - at a vegetable warehouse in the area as they sought the killer. Russia's Investigative Committee said in a statement Tuesday that the suspect, 30-year-old Orkhan Zeynalov, was detained in a town outside Moscow. Investigators did not say what evidence pointed to his involvement in Saturday's slaying. According to Moscow police spokesman Maksim Krolosvetov, Zeynalov confessed to the crime in an "informal conversation" with officers escorting him to Moscow. Tensions have long simmered between ethnic Russians and natives of the Caucasus region, and violence between the two groups has grown more common.