NEW : ` ` I think that today may in fact have been their first mission , '' Robert Gates says . NEW : Vice Joint Chiefs chair says drones help distinguish ` ` friend from foe '' NEW : Gadhafi loyalists ` ` nestle up in crowded areas , '' ' John Cartwright says . NEW : `` It 's very difficult to identify friend from foe , '' Cartwright said , noting that the drones facilitate identification of individuals on the ground . Air force , missile and radar sites , as well as helicopters , are prime targets .
NEW : ` ` I think that today may in fact have been their first mission , '' Robert Gates says . NEW : Vice Joint Chiefs chair says drones help distinguish ` ` friend from foe '' NEW : Gadhafi loyalists ` ` nestle up in crowded areas , '' ' John Cartwright says . NEW : Air force , missile and radar sites , as well as helicopters , are prime targets .