According to the Immigration and Customs Enforcement Office of Detention and Removal
website, the federal agency has only one center for detention in Colorado, a privately owned facility located in Aurora. The website doesn't mention that the agency may also be holding people at unlisted sub-field offices around Colorado.
The Nation, which broke the story last week of such sub-field offices, called them "secret" and suggested that they are "black sites" into which detainees might effectively disappear. ICE disputes the terminology.