Officers from the OMON riot police sealed off the block on Moskovsky Prospekt, blocking entrances and exits, with more than five prisoner-transport vans stationed at the scene, according to a SOTAvision correspondent. People were released one at a time after document checks, and some were driven away.

The raid on Sennoy Market and the prayer hall next to it began after Friday prayers, according to Fontanka, 78.ru and SOTAvision. Citing 78.ru, security forces swept not only the market but also nearby shops, cafes and hostels.

A source in law enforcement told TASS that the prayer hall near the market is attended by about 1,000 worshippers. A source for RIA Novosti described the operation as a "large-scale check of compliance with migration legislation among foreign citizens."

Military commissariat officers took part in the raid, checking whether foreigners who had recently obtained Russian citizenship had registered for military service. "To date, several dozen people have been identified and handed notices to report to the military commissariat for registration for military service," a TASS source said.

One man who left the cordoned area told SOTAvision that after prayers everyone was locked in and officers began checking who was not registered for military service, as well as registration, patents and other documents. According to him, security forces used physical force during the raid.

Another man told 78.ru that he received a notice even though, he said, he was already registered. "They're handing out notices," a witness told Fontanka.

The Telegram channel Baza reported that hundreds of security officers took part in the raid, including special forces and military commissariat staff. Mash reported dozens of detentions. According to 78.ru, several dozen people were detained for various violations. RIA Novosti, citing a source in security structures, reported that those detained were worshippers whose migration documents had been drawn up in violation of the law.

Witnesses told Fontanka that security forces were also inspecting hostels and ethnic cafes in neighboring buildings and checking whether the prayer hall's activities complied with legislation on religious practice.