Russia's Investigative Committee says a heating pipe burst in a hotel in the Urals city of Perm, killing at least five people.
A Committee statement said the deadly blast occurred at the Karamel hotel on January 20.
Interfax quoted a source in the emergency services as saying that one of those killed in the accident was a child.
Three other individuals have been hospitalized with burns, the statement said, adding that a probe had been launched into whether safety standards at the hotel were adequate.