A man was injured in the blast of an unidentified explosive device in the capital of Russia's Republic of Dagestan on Sunday evening. The injured man was hospitalized, a source in the alert force of Makhachkala district police told Itar-Tass on Monday. “The blast went off as a result of the careless handling with the explosive device,” a police report said. The investigation into the incident is underway. The police do not rule out “the explosion could go off during the preparations to a crime.” The injured man is not named in interests of the investigation. A criminal case was instituted over the blast.