(S (S (PP-SBJ (SBAR (S (PP-SBJ (NP (PP (PP (BASENP (NNP 国連) (NNP 平和) (NNP 維持) (NNP 軍)) (IN へ)) (IN の)) (NN 攻撃)) (IN が)) (NP (PP (BASENP (NN だれ)) (IN の)) (NN 責任))) (INFKB か)) (IN は)) (VP (ADVP (RB 未だ)) (VP (VP (VBV わかっ) (INTE て)) (VP (VBO い) (VP (MD ない)))))) (PERIOD 。))
国連 平和 維持 軍 へ の 攻撃 が だれ の 責任 か は 未だ わかっ て い ない 。
It is not yet known who was responsible for the attack on the UN convoy .