(S (S (BASENP (DT The) (NNP Pentagon)) (VP (VBZ has) (VP (VBN confirmed) (SBAR (SBAR (IN that) (S (BASENP (NNP US) (NNS forces)) (VP (VP (VP (VBD began) (NP (BASENP (DT an) (JJ on-going) (NN operation)) (PP (IN of) (BASENP (NNS airstrikes))))) (PP (IN in) (BASENP (JJ southern) (NNP Somalia)))) (PP (IN on) (BASENP (NNP Monday)))))) (CONJP (COMMA ,) (CC and)) (SBAR (IN that) (S (NP (BASENP (DT the) (NNS attacks)) (PRN (COMMA ,) (VP (VBN targeted) (PP (IN at) (BASENP (JJ Islamic) (NN militia)))) (COMMA ,))) (VP (VBP are) (VP (VBG continuing))))))))) (PERIOD .))