(S (S (PP (IN In) (BASENP (DT the) (JJ previous) (NN attack))) (COMMA ,) (S (BASENP (JJ several) (NNS bombs)) (VP (VBD had) (VP (VBN been) (VP (VBN detonated) (PP (IN by) (NP (BASENP (DT the) (NNS attackers)) (COMMA ,) (SBAR (WHNP (WP who)) (S (VP (ADVP (RB also)) (VP (VBD fought) (PP (IN with) (BASENP (JJ Afghan) (NNS commandos)))))))))))))) (PERIOD .))