Ryanair flight 4978 was about to begin its descent to Vilnius in Lithuania on Sunday when it suddenly changed direction after a “security alert,” turning sharply east and descending towards the capital of Belarus, Minsk.Ryanair flight 4978 was about to begin its descent to Vilnius in Lithuania on Sunday when it suddenly changed direction after a “security alert,” turning sharply east and descending towards the capital of Belarus, Minsk.