One of the underground stations affected by Monday's bombing in St Petersburg has been closed after a bomb threat, Russian emergency officials have said.
The agency said Sennaya Ploshchad station had been shut after an anonymous call warning of a bomb.
The blast on Monday happened on a metro train as it travelled between Sennaya Ploshchad and Tekhnologichesky Institut underground stations, killing 14 people.
The seven people were from Central Asian countries and investigators say they were recruiting for IS.
The bombing of a subway train in Russia has drawn condemnation from world leaders.
A blast has ripped through an underground train in Russia's second-largest city on Monday.