BERLIN (AP) — German officials say 13 potential bidders have expressed interest in buying the Hahn regional airport outside Frankfurt after its planned sale to a Chinese company was scrapped amid doubts about the purchaser's reliability.

The state interior ministry in Rhineland-Palatinate said Friday that auditors will evaluate the potential bids by mid-September, clearing the way for formal offers. It didn't identify any of the bidders.

Rhineland-Palatinate planned to sell its 82.5 percent stake in the financially struggling airport to Shanghai Yiqian Trading Company, a logistics and construction company.

But officials pulled the plug on the deal in July because a payment wasn't made, and citing wider doubts about the reliability of the purchaser.