A new migrant detention centre in Florida, planned to open in weeks, will cost about $450m (£332m) a year to run.

EVERGLADES, Florida — President Donald Trump celebrated the speedy construction of “Alligator Alcatraz,” a new immigrant detention facility in the heart of the Florida Everglades, and warned that the only way for detainees to get out of this “treacherous” region is through deportation.

The evocative name refers to a detention, processing and deportation camp for undocumented migrants that sprang up in a blink of an eye in the middle of the Everglades. The airfield site, in Ochopee,