(S (S (BASENP (DT The) (NNP HMRC)) (VP (VBP have) (VP (VBN stated) (SBAR (IN that)) (S (BASENP (PRP they)) (VP (VBP have) (VP (VBN worked) (S (VP (TO to) (VP (VP (VB find) (NP (BASENP (DT the) (NN source)) (PP (IN of) (BASENP (DT the) (JJ illegal) (NNS products))))) (PP (IN during) (NP (BASENP (DT the) (NN time)) (SBAR (IN since) (S (BASENP (DT the) (NN discovery)) (VP (VBD was) (VP (VBN made)))))))))))))))) (PERIOD .))