Russian officials say a small explosive device has injured five people at a bus stop in central Moscow.
The blast occurred late on December 7 in the Chistie Prudy district of Moscow, an area that has numerous bars and cafes.
Russian police downplayed suggestions that the blast was the result of a terrorist attack, saying that a "hooliganism investigation" had been opened into the case.
Interior Minister spokesman Andrei Galiakberov said it could have been a small explosive thrown from a passing car or a window of a nearby building.
He said the five were injured by broken glass.
Russian news agencies earlier reported that two of the injured were women who were taken to hospital with leg injuries, while a third injured woman refused to be hospitalized.