The FBI told us they found no trace of explosives at the crash sites.
( ( The FBI ) ( ( ( told us ) ( they ( ( found ( ( no trace ) ( of explosives ) ) ) ( at ( the ( crash sites ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT The) (NNP FBI)) (VP (VBD told) (NP (PRP us)) (SBAR (S (NP (PRP they)) (VP (VBD found) (NP (NP (DT no) (NN trace)) (PP (IN of) (NP (NNS explosives)))) (PP (IN at) (NP (DT the) (NN crash) (NNS sites))))))) (. .)))
The FBI  found 10,000 pounds of explosives in the wreckage.
( ( The FBI ) ( ( ( found ( ( 10,000 pounds ) ( of explosives ) ) ) ( in ( the wreckage ) ) ) . ) )
(ROOT (S (NP (DT The) (NNP FBI)) (VP (VBD found) (NP (NP (CD 10,000) (NNS pounds)) (PP (IN of) (NP (NNS explosives)))) (PP (IN in) (NP (DT the) (NN wreckage)))) (. .)))