Updated at 12:45 p.m. ET
A lone gunman opened fire near the headquarters of the FSB, Russia's Federal Security Service, on Thursday night, killing at least one person before authorities were able to "neutralize" the attacker, according to reports.
The incident took place within hours of Russian President Vladimir Putin's annual news conference.
Multiple eyewitness reports said the gunfire came from near the main FSB building — formerly the KGB — on Lubyanka Square. The location is a short distance from the Kremlin.