Pyongyang, September 20 (KCNA) -- The U.S. imperialists and the south Korean puppet air force started the madcap air refueling drill in the sky above the West Sea of Korea from Sept. 16, according to KBS of south Korea.

Involved in the drill which will last till Sept. 30 are KC-135 of the U.S. imperialist aggression forces and F-15Ks and KF-16s of the puppet air force.

The exercise targeted against the DPRK is straining the situation.