▁A ▁pre lim inary ▁analysis ▁of ▁air ▁samples ▁from ▁North ▁Korea ▁shows ▁' radio active ▁de br is ▁consistent ▁with ▁a ▁North ▁Korea ▁nuclear ▁test ', ▁according ▁to ▁a ▁statement ▁from ▁the ▁office ▁of ▁the ▁top ▁U . S . ▁intelligence ▁official . ▁The ▁statement , ▁from ▁the ▁office ▁of ▁Director ▁of ▁National ▁Int elligence ▁John ▁Neg ro pon te , ▁was ▁sent ▁to ▁Capit ol ▁Hill ▁but ▁not ▁released ▁public ly . ▁CNN ▁obtained ▁it ▁from ▁a ▁con gression al ▁source . ▁The ▁national ▁intelligence ▁office ▁statement ▁said ▁the ▁air ▁samples ▁were ▁collected ▁Wed nes day , ▁and ▁analysis ▁found ▁de br is ▁that ▁would ▁be ▁consistent ▁with ▁a ▁nuclear ▁test ▁' in ▁the ▁vic inity ▁of ▁P ung gy e ' ▁on ▁Monday . ▁The ▁South ▁Korean ▁Def ense ▁Ministry ▁told ▁CNN ▁that ▁the ▁United ▁States ▁has ▁informed ▁it ▁that ▁radio activity ▁has ▁been ▁detected ." ▁The ▁aircraft ▁was ▁based ▁at ▁Off utt ▁A FB ▁and ▁was ▁sent ▁to ▁K ad ena ▁Air ▁Base ▁on ▁Ok ina wa ▁to ▁operate ▁during ▁the ▁sampling ▁miss ions . ▁ ▁On ▁June ▁ 1 7 , ▁ 2 0 0 9 , ▁Jo ong Ang ▁Daily ▁reported , ▁in ▁reference ▁to ▁a ▁pur port ed ▁May ▁ 2 5 ▁nuclear ▁test ▁by ▁North ▁Korea : ▁" The ▁U . S . ▁Air ▁Force ▁twice ▁dispatch ed ▁a ▁special ▁reconna issance ▁jet , ▁the ▁W C - 1 3 5 ▁Constant ▁Phoenix ▁from ▁K ad ena ▁Air ▁Base ▁in ▁Ok ina wa , ▁Japan ,