On 29 March 2013, two Tu-22M3 bombers flying in international airspace made a simulated attack on Sweden. The Swedish air defense failed to respond. Two Tu-22Ms flew supersonic over the Baltic Sea on 24 March 2015. Two Tu-22Ms approached Öland in international airspace on 21 May 2015. The Swedish Air Force sent two Saab JAS 39 Gripen fighters to mark their presence. On 4 July 2015, two Tu-22Ms approached the Swedish island of Gotland without violating its airspace, followed by Swedish and other fighter aircraft.