A blast in a St. Petersburg train carriage on Monday that killed 14 people and wounded 50 was probably carried out by a Russian citizen born in Kyrgyzstan, authorities from the predominantly Muslim central Asian state said.
Russian news agency RIA Novosti reported on Tuesday that authorities had received a warning of a possible second attack at the same Sennaya Ploshchad metro station. Interfax news agency said several fire engines were outside the station, which had been closed.
The explosion on Monday was a suspected suicide bombing by a perpetrator with ties to radical Islamists, Interfax cited a law enforcement source as saying. A spokesman for the Kyrgyz GKNB security service identified the suspect as Akbarzhon Jalilov, born in the city of Osh in 1995, but provided no other details.