In a letter dated Feb 7th 2000, NATO Secetary General Lord Robertson confirmed to UN Secretary General Kofi annan the details of DU ammunition use in the 1999 Kosovo war:

"DU rounds were used whenever the A-10 engaged armour during Operation Allied Force.  Therefore, it was used throughout Kosovo during approximately 100 missions.  The GAU-8/A AP1 round is designated PGU-13/B and uses a streamlined projectile housing a sub-calibre kinetic energy penetrator machined from DU, a non critical by-product of the uranium refining process.  The A10s used DU rounds as part of their standard load.  A total of approximately 31,000 rounds of DU ammunition was used in Operation Allied Force.

The major focus of these operations was in an area west of the Pec-Dakovica-Prizren highway, in the area surrounding Klina; in the area surrounding Prizren and in an area north of a line joining Suva Reka and Urosevac.  However, amny missions using DU also took place outside of these areas.  At this moment it is impossible to state accurately every location where DU ammunition was used.