HARTFORD, Conn. (AP) – Elite libraries have told federal investigators that more antique maps are missing than those stolen by E. Forbes Smiley III, a part-time Mainer who admitted in June to taking nearly 100 maps.

The British Library, Yale and Harvard report more maps missing from their collections than those the map dealer has admitted to taking. The most valuable maps are within Smiley’s area of interest – early maps of North America – and several are copies of maps he has admitted stealing.

“We continue to entertain serious doubts about the completeness of the investigation and the extent of Mr. Smiley’s cooperation with the authorities,” Clive Field, director of scholarship and collections at the British Library, recently wrote to the FBI. “We note that he has admitted to stealing only one map from our collections but are not persuaded that this exhausts the limits of Mr. Smiley’s involvement in our thefts.”

Smiley, 50, pleaded guilty in U.S. District Court in New Haven on June 22 to one count of theft of major artwork in the theft of a map from Yale University. Smiley is from Chilmark, Mass., and has a summer home on Sebec Lake in Sebec, Maine.

He admitted taking 97 maps over eight years from the New York and Boston public libraries, the Newberry Library in Chicago, Harvard University library and British Library in London.

The British Library suspects Smiley of taking three additional maps and has hired a Philadelphia lawyer to take up its case.

On Friday, Harvard released the names of five additional maps missing from its collection, following the lead of Yale and the British Library in making its thefts public.

Richard Reeve, Smiley’s lawyer, said his client has furnished complete information to the FBI and worries that the libraries have found a scapegoat on whom to pin additional thefts.

“Either the maps have legs themselves or there are other people taking maps,” he said.

Federal authorities have defended their work and invited the libraries to produce additional evidence.

“If they’re uncovering more information, we’ll be more than happy to take a look,” said Tom Carson, a spokesman for Connecticut’s U.S. attorney.

Librarians and the FBI are scheduled to meet in New Haven on Aug. 7 to sort out issues related to the case before Smiley’s sentencing in September. He faces up to six years in prison, but the judge could impose more jail time if proof emerges that he stole more than the nearly 100 he has already confessed to taking.

The oldest maps dated to the 1500s and some are the first records of settlements, territories and discoveries in America, experts say.

Poor record-keeping by the libraries limited the FBI’s investigation. Investigators also had difficulty tracing maps, which were printed in multiple copies, to a single owner.

Investigators say that without Smiley’s cooperation they would have recovered only a fraction of the maps they ultimately obtained.