Hunt Auctions has stopped the bidding and removed lots from its current auction containing 19th-century letters sent to Harry Wright while the FBI investigates whether they were among items stolen from the New York Public Library years ago. Wright, built the first professional baseball team in Cincinnati.

According to the Associated Press, the FBI said investigators are trying to determine “whether those items were among the items apparently stolen from the public library collection.” The 20-plus lots were part of Hunt’s live auction during FanFest on July 14.

The library once contained four scrapbooks of letters that had been sent to Wright between 1865-94. Only one of those volumes, covering the years 1878-84, remain at the library. The material was found missing during an assessment of the collection in 1986-87.

Hunt Auctions did not identify the seller of the letters, stating they had belonged to the consignor’s grandparents.