 After the two helicopters were spotted by a Yugoslav Air Force tracking radar near Bihać, a pair of Mikoyan-Gurevich MiG-21s, which were on standby at the Željava Air Base near Bihać, were ordered to take off and intercept the aircraft.The MiG-21s, assigned to the 125th Squadron of the 117th Fighter Aviation Regiment, were piloted by Lieutenant Emir Šišić and Captain Danijel Borović.However, Borović declared that his aircraft had a problem with its engine, and Šišić took off alone.