Six men have been detained in St. Petersburg on charges of abetting terrorism, Russia's Investigative Committee has confirmed.
The men, who are described as migrant workers from Central Asia, are suspected of attempting to recruit other Central Asian migrants in St. Petersburg to join terrorist groups.
Police believe that the suspects could have been working since November 2015 in a bid to find recruits who could commit terrorist attacks for groups such as the Islamic State and Al-Nusra. They allegedly also worked to send young men abroad to fight with terrorist groups.
In a statement, the Investigative Committee said that they had found no link between the men and Monday's terrorist attack in St. Petersburg, but emphasized that investigators would “check all channels and contacts.”
Fourteen people died on Monday when 22-year-old Akbarzhon Dzhalilov, a Kyrgyz-born Russian citizen, detonated a bomb in a St. Petersburg subway car.
Russia has announced three days of official mourning to mark the event, which left more than 50 people injured.