The exercises are carried out in the Estonian Defence Forces' central training area in Tapa, Lääne-Viru County. The B-52s will drop 500-pound guided bombs in air-ground attack exercises.

"Cooperation practice with heavy bombers are a good opportunity to practice massive air strikes against ground targets," acting chief of the Estonian Air Force, Col. Riivo Valge, said on Thursday.

In addition to Estonian, Latvian, and Lithuanian personnel, members of other allied units will also participate in the exercise, the Defence Forces reported.

The U.S. Air Force's B-52 Stratofortress bombers have been in service since early 1955. The planes were part of the United States' nuclear deterrent during the cold war before the USA switched to intercontinental ballistic missiles as the preferred means to deliver a nuclear strike.

They can carry up to 32,000 kg of weapons at a typical combat range of more than 14,000 km. Their top speed, though still subsonic, is very high at 1,047 km/h. They can be refueled in the air if needed.

More than 50 planes of the type are still in regular operation and beyond regular maintenance are continuously modernized. Despite more than five decades of service history, the B-52s are expected to be around until 2045, by which time they will be phased out and replaced.