An RC-135U Combat Sent, designed to collect technical intelligence on adversary radar emitter systems was spotted in German airspace at 7:40 a.m. Moscow time (4:40 a.m. GMT), PlaneRadar reported posting a map with the plane's route.
The US plane flew above the Kaliningrad Region border at 8:35 a.m. Moscow time (5:35 a.m. GMT).
For months, US aircraft have reportedly been seen over the Black Sea, near the Kaliningrad Region, and also near Russian bases in Syria. The Pentagon has refused to stop intelligence operations close to Russia's borders, despite calls from the Russian Ministry of Defence.