SPOKANE, Wash. (AP) — A gigantic, Amazon-like warehouse could be headed to vacant fields around the Spokane International Airport.

The Spokesman-Review reports a company has submitted conceptual plans for a four-story warehouse to the Spokane County Building and Planning Department. The warehouse would contain 2.5 million square feet of space.

The company is not identified in documents filed with the county.

Amazon is expanding the number of fulfillment centers it operates around the country. The size of the warehouse hints at something Amazon-like, and the company's fulfillment centers often employ 1,000 or more workers to pack and ship products.

An Amazon spokeswoman declined to comment.

Coffman Engineers is listed as the applicant for the warehouse. But the company has signed a nondisclosure agreement and can't discuss the project, said Karl Kolb, general manager of Coffman's Spokane office.