A blast in an upscale residential block in Moscow killed one person and wounded four others on Monday morning, Russian news agencies reported, citing emergency officials.
Those wounded in the blast, the cause of which was not revealed, were hospitalized in grave condition, Russia's state news agency RIA Novosti reported, citing Moscow health officials.
Footage released by Russia's main investigative agency, the Investigative Committee, showed a building hall with glass doors shattered and suspended ceilings torn up.
The Committee said it opened a criminal probe into the explosion on the charges of murder by means injurious to the public and attempted murder of two or more people.
Russian state news agencies Tass and RIA Novosti, citing law enforcement sources, identified one of the wounded as Armen Sarkisyan, the founder of a volunteer battalion that is fighting in Ukraine and the head of a boxing federation in the Russian-controlled part of Ukraine's Donetsk region.
Sarkisyan is on a wanted list in Ukraine, according to RIA Novosti, but the agency did not say on what charges.
Tass reported that Sarkisyan's bodyguard was killed by the blast.
