Residents of four counties in Lubelszczyzna, Poland, reported hearing a strange engine sound in the sky, with reports coming from areas near the borders with Belarus and Ukraine to as far as Lublin. Despite a two-day search, no source of the sound has been identified. Authorities have found no traces indicating the origin of the sound. Former Air Force Inspector General Tomasz Drewniak stated to WP that no surveillance system can detect everything happening in the airspace at all times. The incident has sparked curiosity and speculation among locals regarding the nature of the sound and what may have caused it. The investigation remains open, with no definitive explanation currently available. The lack of physical evidence complicates efforts to determine the source of the mysterious aerial phenomenon.