The shooting happened while Russia's President Vladimir Putin was at a concert for security forces in the Kremlin.
At least one person has died after a person opened fire near the headquarters of Russia's spy agency.
Early reports recorded a higher number of fatalities, citing three people dead, as well as uncertainty over whether the shooting happened in or near the building.
The agency, the Federal Security Service but better known as the FSB and formerly known as the KGB, have said through Russian press that the shooter has been "neutralised" and that there a number of people wounded.
A Russian TV channel, RT TV, have said the Russian intelligence services have said the incident is "an act of terrorism".
A gunman opened fire on the headquarters of Russia's FSB security service i...
Three people were killed in a shooting in central Moscow on Thursday evening near the headquarters of Russia’s FSB security service headquarters, the Izvestia newspaper reported, citing a source.
Earlier on Thursday, a witness told Reuters she had heard gun shots fired in the same area and a video shared on social media showed several people resembling police officers holding assault rifles running down a nearby street.
FSB shooting: Man opens fire near HQ of Russian intelligence in central Moscow, one FSB staff killed
Gunfire has broken out near central Moscow's Lubyanka Square in the immediate vicinity of the Federal Security Service building. The authorities said the gunman was neutralized and two FSB officers seriously injured.
Gunfire has broken out near central Moscow's Lubyanka Square in the immediate vicinity of the Federal Security Service building. The authorities said the gunman was neutralized and two FSB officers wounded.
The shooting occurred around 6 p.m local time right at the heart of Russia’s capital on a street leading to the square and the iconic FSB building and some 10 minutes on foot from the Kremlin.