GARDEN CITY, N.Y. —  A one-time director of the Theodore Roosevelt Association stole and tried to auction off one of its prized artifacts _ a 1918 letter the former president wrote about his son Quentin's death in World War I, prosecutors said.

Edward Renehan Jr., a historian who has written six books, was charged Wednesday with grand larceny, criminal possession of stolen property and criminal possession of a forged instrument. The last charge referred to what authorities said was a phony letter claiming the association had given Renehan the Roosevelt note.

Renehan was released without bail pending an April 21 court date. His lawyer, Peter Brill, said the 51-year-old had been diagnosed last summer with bipolar disorder.

Philip Roosevelt, an association board member and cousin of the 26th president, said the allegations seemed "completely at odds with the Ed that I have known."

Tweed Roosevelt, a great-grandson of the former president, said the allegations, if true, would represent a "disgraceful" breach of trust.

Prosecutors said Renehan took the letter between March 2005 and July 2006 from the Roosevelt association's headquarters in Oyster Bay, on Long Island. At the time, he was the organization's acting executive director.

The letter has been returned, but investigators are probing whether any other items were taken, said Nassau County Assistant District Attorney William Wallace.

In December 2006, a Florida postal worker pleaded guilty to stealing a gun Roosevelt used in the Spanish-American War. It was taken from the Sagamore Hill National Historical Site, the former president's former home in Oyster Bay. The gun was recovered.

The Theodore Roosevelt Association aims to preserve the former president's memory and protect artifacts, papers and places associated with him.

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