The Russian Federal Security Service (FSB) says it has arrested seven suspected Islamic extremists and thwarted plans for bomb attacks in St. Petersburg on December 16.
The FSB said on December 15 that the suspects were detained in St. Petersburg on December 13-14, and alleged that they were planning to set off several explosions, including a suicide bombing.
It said they were suspected members of the extremist group Islamic State (IS) and that they were being directed from abroad via the messaging app Telegram.
The statement comes just three days after the FSB announced that three suspected members of a similar group were arrested outside Moscow, where they were allegedly plotting attacks during the New Year holidays and the upcoming presidential campaign.
The FSB frequently announces that it has foiled terrorist plots ahead of holidays and important events.
President Vladimir Putin announced last week that he would seek a new six-year term in the March 18 election.
A blast that the authorities said was a suicide bombing killed 16 people on a subway train in St. Petersburg in April.
Based on reporting by RIA and Interfax