sentences:  In 1955 the Bezmer Air Base hosted the 22 Fighter Air Regiment, later transformed into 22 Fighter-Bomber Air Regiment, and eventually into 22 Attack Air Base of the Bulgarian Air Force, serving as a base for Su-25 Frogfoot ground attack aircraft, as well as Su-22М-4 and Su-22UM-3K reconnaissance planes.Aircraft and personnel from Bezmer have recently been participating in a number of joint military exercises including the PfP ‘Cooperative Key’ in Turkey, Bulgaria, Romania and France, ‘Immediate Response 2005’ and the Bulgarian-American-Romanian ‘Immediate Response 2006’.Aircraft and personnel from Bezmer have recently been participating in a number of joint military exercises including the PfP "Cooperative Key" in Turkey, Bulgaria, Romania and France, ‘Immediate Response 2005’ and the Bulgarian-American-Romanian "Immediate Response 2006".