AP Photo

A federal judge on Wednesday blocked the most controversial parts of Arizona's immigration enforcement law from going into effect, a ruling that at least temporarily squashed a state policy that had inflamed the national debate over immigration.

Judge Susan Bolton of Federal District Court issued a preliminary injunction against sections of the law, scheduled to take effect on Thursday, that called for police officers to check a person’s immigration status while enforcing other laws and required immigrants to prove that they were authorized to be in the country or risk state charges. She issued the injunction in response to a legal challenge brought against the law by the Obama administration.