A powerful explosion in a Monaco residential building Monday evening injured three members of a Ukrainian family, including businessman Vadim Iermolaiev, seriously. Authorities are investigating the incident as a potential bombing. A primary suspect is currently at large, and a manhunt is underway. Initial reports from French news outlets *Le Figaro* and *Le Parisien* indicate the explosion occurred within the building itself. The extent of the injuries sustained by the family members has not been fully disclosed, but Iermolaiev is reported to be critically wounded. Investigators are working to determine the cause of the blast and identify the motive behind the potential attack. The incident has prompted a significant security response in the Principality.