One person was killed and three others were wounded at the Menshevik confectionary factory in southeastern Moscow, a law enforcement source told TASS on Wednesday.
"One person died in the shooting and three others were wounded," the source said.
According to preliminary data, "a former owner came to the factory, shot dead a security guard and is now walking with weapons around the premises and is shooting," the source said.
The factory’s premises have been cordoned off, and hostages may be held inside the building, the source said. Special police forces have been deployed to the scene.