Florida lawmakers worried about “humanitarian concerns” were denied entry into the new detention center dubbed as “Alligator Alcatraz” Thursday, just hours after the arrival of its first group of detainees.

A group of Florida Democratic state lawmakers was blocked from entering the Alligator Alcatraz immigrant detention facility in the Everglades Thursday, despite citing legal authority for an official legislative site visit.

State law says members of the Legislature are allowed to “visit at their pleasure all state correctional institutions.”