Complex sentence: New England art thief Myles J. Connor Jr., in jail at the time of the robbery, has stated that he and associate Bobby Donati eyed the museum in the 1980s and Donati oversaw the operation.
Split into simpler sentences: New England art thief Myles J. Connor Jr. may have been involved, although he was in jail at the time of the robbery. He has stated that he and associate Bobby Donati eyed the museum in the 1980s and Donati oversaw the operation.