(S (S (BASENP (NNS Explosions)) (VP (VBD were) (VP (VBN felt) (PP (PP (PP (IN in) (BASENP (NNP Tirana))) (CC and) (PP (IN in) (BASENP (NNP Durres)))) (COMMA ,) (NP (NP (BASENP (NN 20km)) (PRN (LRB -LRB-) (BASENP (NN 12) (NNS miles)) (RRB -RRB-))) (PP (IN from) (BASENP (DT the) (NN base)))))))) (PERIOD .))