Gillian Christensen, a spokeswoman with Immigration and Customs Enforcement, said ICE has reviewed "several hundred cases" of immigrants being held in jails around the country and released them in the last week.
They have been "placed on an appropriate, more cost-effective form of supervised release," she said.
Christensen said the agency's "priority for detention remains on serious criminal offenders and other individuals who pose a significant threat to public safety." She did not say how released immigrants were selected or what jails they were released from.
The Governor's Office sent the following statement from Brewer to ABC15:
"I'm appalled to learn the U.S. Department of Homeland Security has begun to release hundreds of illegal aliens from custody, the first of potentially thousands to soon be freed under the guise of federal budget cuts. This is pure political posturing and the height of absurdity given that the releases are being granted before the federal ‘sequestration' cuts have even gone into effect.
"This represents a return to exactly the kind of catch-and-release procedures that have long made a mockery of our country's immigration system. The news is especially concerning when coupled with DHS' acknowledgment today that it may not be able to maintain operation of 34,000 immigration jail beds, as mandated by Congress.
"Everyone knows the federal government must get a handle on spending, and it is well past time that the President begin working with Congress to find real budget solutions. But we cannot let public safety and the rule of law be collateral damage of the President's failed leadership to pass a budget."