 Six J-21 Jastrebs of the Republika Srpska Air Force were engaged by USAF F-16s during Operation Deny Flight.In what would become known as the Banja Luka incident, the Jastrebs were engaged after violating the NATO-enforced no-fly-zone.The USAF claimed 4 J-21s as being shot down by F-16s, while the Serbs claimed 5 Jastrebs as lost.