Two U.S. Air Force B-1B Lancer strategic bombers, after a transatlantic flight, conducted training bombing at the Tapa training ground in Estonia, the Pentagon said on Wednesday.

According to a 28th Bomb Wing press release, the flight, which lasted more than 25 hours, included integration and interoperability training with Danish F-16s overflying Bornholm Island in the Baltic Sea. The B-1s also worked with Estonian Joint Terminal Air Controllers to provide training with inert devices at Tapa Range before conducting a formation low approach at Tallinn Airport, Estonia.

Russian news agency Interfax said that Tapa training ground is located close to Russia’s western flank, about 100 km from the borders of the Leningrad region.

The aerial bombers’ exercise was integrated with Spring Storm live firing exercises, which provided an opportunity to coordinate ground and air fire in cooperation with NATO allies.

The exercise’s main goal was to practice the coordination of air and ground units, where joint terminal attack controllers play an important role in the integration of the two, directing combat aircraft strikes from the front line, the Estonian Defense Forces said.

Forward bomber presence demonstrates the Air Force’s ability to execute flying missions, sustain readiness, contribute to stability in the European theater and sends a clear deterrence message to any potential adversary. These missions also allow the U.S. Department of Defense to meet global security objectives.

“Our crews gain valuable experience operating in a region that some had not seen previously,” said Col. Richard Barksdale, the 28th Operations Group commander. “This mission honed integration with NATO allies and regional partners, and demonstrated our ability to effortlessly shift operations from one area of the globe to another in a short period of time.”

The B-1 can rapidly deliver massive quantities of precision and non-precision weapons against any adversary, anywhere in the world, at any time.