Immigration and Customs Enforcement (ICE) may be moving forward with its reported plans to buy up vacant Amazon-style warehouses to create “mega” detention centers, new procurement records reviewed by the Lever reveal.

On Friday, the agency inked a new $29.9 million contract for “concept design” for “processing centers and mega centers throughout the United States.” This document appears to be the first step toward realizing the agency’s alleged plans to retrofit warehouse space as detention facilities for immigrants in its custody, a development that NBC reported last month, citing internal agency sources.

The “mega detention centers,” utilizing warehouse space, could theoretically be more than twice as large as ICE’s current detention centers on average, per the NBC report. Already, ICE maintains a vast network of hundreds of detention centers across the country, most privately operated, which currently hold around 65,000 people. These facilities range from small temporary holding sites to prisons that jail hundreds of people.