A Russian SU-24 bomber violated Swedish airspace near the strategic Baltic Sea island of Gotland, leaving only after Sweden scrambled two JAS-39 fighter jets, Sweden's military said on Saturday.
The incident on Friday occurred three months after the Scandinavian country became a full member of NATO, dropping two centuries of military non-alliance.
"On Friday afternoon, a Russian SU-24 jet fighter violated Swedish airspace east of Gotland's southern tip. The Swedish air combat command warned the Russian aircraft with a verbal call," the Swedish armed forces said.
"When this was not heeded and the aircraft did not deviate from its route, it was dismissed from Swedish airspace by two JAS-39 Gripens," it said.
The violation was "brief", the military said.
"The Russian actions are not acceptable and demonstrate a lack of respect for our territorial integrity," the head of Sweden's air force, Jonas Wikman, said.
Gotland is located fewer than 350 kilometres (217 miles) from the Russian exclave of Kaliningrad.
Swedish military doctrine holds that whoever controls Gotland is able to broadly control air and naval movements in the Baltic Sea.
Sweden reopened its garrison on Gotland in 2018 after years of slashed military spending saw it close in 2004.
Russia's unilateral annexation of the Crimean peninsula in 2014 had prompted Sweden to start beefing up its military again.
Moscow's full-scale invasion of Ukraine in 2022 then led to Sweden's historic decision to join the NATO military alliance.
The last time Russia violated Swedish airspace was in March 2022, when Swedish fighters intercepted two Su-24 and two Su-27 fighter jets over Gotland.