An employee at a northwest Indiana library found a gun inside a hollowed-out book donated to the branch.
Police in Valparaiso are holding the gun as evidence.
Assistant Library Director Phyllis Nelson says an employee at the Valparaiso branch of the Porter County Public Library discovered the antique-looking firearm when she opened the book earlier this week.
Police describe the weapon as a gold, wooden handled, 31-caliber, single shot, black powder gun.
Nelson says librarians have no way of knowing who donated the book. She says thousands of books are donated each month and no records are kept.
Police have determined the gun was not stolen.
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