BALTIMORE (WJZ)– The man who admitted to stealing hundreds of historical documents from museums up and down the East Coast– including here in Maryland– may have sold some of them. Now, federal investigators are trying to get the priceless pieces back.

Mary Bubala reports.

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Federal investigators are reaching out to collectors and dealers who may have unknowingly bought stolen items from Barry Landau, the disgraced presidential memorabilia collector.

The 63-year-old pleaded guilty last month to charges of conspiracy and theft. Landau and an accomplice are accused of stealing from archives in several states, including the Maryland Historical Society.

“They saw we were a fairly small operation and they thought they had a golden opportunity to rob us blind,” David Angerhofer, a librarian at the Maryland Historical Society, said.

Thousands of documents and objects seized from Landau’s Manhattan apartment have been traced back to libraries and museums, including letters from Abraham Lincoln, Benjamin Franklin, Karl Marx and Franklin D. Roosevelt.

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Landau also admitted to stealing inaugural invitations, a paper from Andrew Jackson and a land grant signed by Lincoln worth more than a million dollars.

“In terms of their value to America, they are priceless,” Pat Anderson of the Maryland Historical Society said.

As part of his plea deal, Landau must also help investigators connect seized documents with their rightful owners and track down items he may have sold.

Landau faces up to 10 years in prison when he’s sentenced in May.

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Landau’s assistant, 24-year-old Jason Savedoff, also pleaded guilty to theft in this case.