Rockefeller, who police say uses a range of aliases, may have been heading from New York City to Long Island to pick up a recently purchased boat called "Serenity," according to Boston police, one of several law enforcement agencies in two states working to catch Rockefeller and safely reunite the child with her mother, Sandra Boss.
Boston police detectives are sorting through stories that Rockefeller told friends in Boston about wanting to travel to Alaska, Peru, and Bermuda on the yacht, according to a high-ranking police official with direct knowledge of the case. The official confirmed to ABCNews.com that Clark Rockefeller told an aquaintance that he used "$300,000 in gold bars" to buy the boat.
Authorities are also looking into a possible credit card purchase in which Rockefeller bought two pairs of matching father-daughter outfits, the official said.
Boston police released images this afternoon of a pair of dresses that Rockefeller recently bought that Reigh might be wearing.
Montgomery, the Coast Guard spokesman, declined to offer additional details about the search for the catamaran, which would be capable of long trips, including ones to Bermuda or the Caribbean.
Even if Rockefeller succeeds in leaving port to make a run for a foreign country by sea, local authorities may be waiting for his arrival. Douglas McNabb, a criminal defense lawyer who specializes in international extradition, told ABCNews.com that local authorities in foreign countries typically cooperate with U.S. law enforcement to track down, arrest and extradite fugitives.
Though Rockefeller is not a descendant of John D. Rockefeller, the wealthy New York industrialist, he apparently did not dissuade other people from assuming they may be related.
When the Rev. Brian Marsh of Trinity Church in Cornish, where Rockefeller and Boss attended church until about two years ago, asked about Rockefeller's famous last name, he said Rockefeller didn't answer him directly.
Instead, he took out a pocketknife with the name "Nelson Rockefeller" on it, Marsh said. "He implied a connection."
John Hammond, chairman of the local board of selectmen in Cornish, said Rockefeller claimed he worked as a physicist. "Things were always kind of vague with him," Hammond said. "I never got concrete answers. He never really talked in specifics."
Fraser Seitel, a spokesman for the John D. Rockefeller family, told ABCNews.com that Clark Rockefeller is not a descendant of the wealthy industrialist family of New York.
Boston police say the kidnapping suspect has used several names in the past, including J.P. Clark Rockefeller, James Frederick, Clark Mill Rockefeller and Michael Brown.
Detectives are working on trying to determine the work history and identity of Rockefeller. "We have a team assigned to work 'Who is Clark Rockefeller?' No one seems to know who this guy really is,'' said the official with knowledge of the case.
Clark Rockefeller and Boss, who reportedly married in the early 1990s on the Massachusetts island of Nantucket, divorced in 2007. A judge impounded the divorce case file at the couple's request.
Boss, an executive level consultant who attended Harvard Business School, was awarded custody of their daughter and successfully changed the child's name from Reigh Rockefeller to Reigh Boss.