Complex sentence: Loeb, the publisher of the "Manchester Union Leader", maintained that the letter was not a fabrication, but later admitted to having some doubt, however, after receiving another letter claiming that someone had been paid $1,000 to write the Canuck Letter.
Split into simpler sentences: Loeb, the publisher of the "Manchester Union Leader", maintained that the letter was not a fabrication. Loeb later admitted of some doubt, however, after receiving another letter claiming that someone had been paid $1,000 to write the Canuck Letter.