Japan said its warplanes used flares to warn a Russian reconnaissance aircraft to leave northern Japanese airspace on Monday.

The Russian Il-38 maritime patrol and anti-submarine warfare aircraft flew north of Rebun Island three times from 1 p.m. and 4 p.m., violating Japanese airspace with each encroachment lasting for 30 seconds to one minute, the defense ministry in Japan reported.

Japanese fighter jets fired warning flares at a Russian reconnaissance plane after it repeatedly breached the neighbouring country’s airspace, Tokyo said, as tensions rise over Moscow’s increasing military cooperation with China in the region.