Russia's federal migration service has introduced civilian patrols as part of a crackdown on illegal immigrants.
Civic-minded citizens in Moscow can now sign up to take part in organised raids of migrant housing and street patrols.
The volunteers are supervised by a migration service official and not allowed to use force, unless in self-defence.
Sky News filmed a raid on a suspected migrant workers' camp in a suburb on the outskirts of Moscow.
The volunteers gathered in a supermarket car park at 6am. It was snowing heavily and the temperature was -10C, but the group seemed enthusiastic as they piled out of their 4x4s to discuss the plan.
We set off in convoy towards the camp along a rough track deep in snow. We were told the area is close to a large open-air market where many of the migrants find work.