Earlier this week, New York City's Department of Consumer Affairs began investigating allegations that autographs and other sports memorabilia being sold on the auction site were fake. That probe has now reportedly expanded into sales of china, porcelain and ceramics, according to the New York Post.

Since the probe began, eBay has insisted it is not responsible for any fake merchandise because it is merely the middleman. The company recently stepped up its efforts to stop fraud.

Authorities believe eBay bears some responsibility because it receives a commission from every sale. Officials are also investigating claims from a porcelain expert who said eBay brushed off his complaints that fraudulent items were being sold there.

EBay has declined to specifically comment on New York's investigation, but late Thursday the company promised to work with law enforcement and other officials investigating the fraud complaints.