Russia's counter-terrorism agency has arrested a group of people who were preparing a terrorist attack in central Moscow, it said in a statement on Sunday (11 October), which was carried by the TASS news agency. "At the flat where the bandits were hiding, an improvised explosive device was found and defused," the National Anti-Terrorism Committee said.

They did not provide details about the identities of the suspects, but a law enforcement agency source told TASS that ten people are being investigated. According to local media, more than 100 residents in the building the suspects were preparing in were evacuated during Sunday's raid. Supplies of natural gas were cut off during the duration of the operation.

Russia recently began launching air strikes in Syria in order to bolster Syrian President Bashar al-Assad's government forces. Its involvement has been branded as "fundamentally flawed" by the US, with the Kremlin facing accusations that it is ignoring Islamic State (Isis) fighters to go after al-Assad's opponents.

Security experts have also warned that Russia's involvement in Syria's civil war could make the country a target for Islamic extremists who will make increased attempts to recruit and radicalise Russian Muslims. Around 2,400 Russian citizens are thought to have joined Islamic State, which now controls large swathes of Syria and Iraq.