The Federal Migration Service has conducted raids on construction sites around the city and in the Moscow region, in concert with public oversight organizations.
About 400 foreigners who were in violation of migration rules were uncovered in the raids, which took place Friday, Interfax reported.
Roughly 75 employers were cited for violations of migration law and about 8 million rubles ($250,000) in fines were issued, the service's media department said.
The raids took place at an office complex under construction on Ulitsa Mozhaisky Val and at construction sites in the Novomoskovsky and Troitsky districts in the region.
"It's necessary that the migration situation does not bring social tensions," said Vladimir Shaposhnikov, a member of the president's human rights council, which participated in the raids.