CHICAGO (AP) — A federal appeals court has temporarily blocked the immediate release of hundreds of immigrants detained during a Chicago immigration crackdown in a split decision announced Thursday. The ruling also allows for the continuation of a consent decree that outlines how federal immigration agents can perform arrests without warrants.

During a hearing last week, the 7th U.S. Circuit Court of Appeals examined a 2022 agreement that governs how U.S. Immigration and Customs Enforcement (ICE) can arrest immigrants outside of explicitly targeted operations. This decree gained prominence amid the increased Chicago-area immigration enforcement actions that have resulted in more than 4,000 arrests since its inception.

Last month, U.S. District Judge Jeffrey Cummings had ordered the release of over 600 immigrants on bond, citing a violation of the previous agreement by the government. However, the appeals court has put that order on hold, keeping roughly 450 individuals in custody.

In a 2-1 decision, the appeals court stated that Judge Cummings overstepped his boundaries by ordering a blanket release without evaluating each detainee's case individually. The opinion emphasized that the consent decree carefully delineates what the district judge can or cannot mandate, balancing enforcement with public safety. Importantly, it concluded that the Trump administration had incorrectly classified all immigrant arrestees as subject to mandatory detention.

Attorneys for the plaintiffs expressed their disappointment with the current ruling but indicated they were pleased the court upheld the extension of the agreement, which necessitates that ICE present documentation for each arrest. Similar actions have been taken by federal judges in other regions, including Colorado, to restrict warrantless arrests.

With many detainees facing deportation without being fully aware of their options, attorneys are pushing for quick legal decisions. The detainees were primarily arrested during the 'Operation Midway Blitz' immigration crackdown over the summer and into the early fall. Legal representatives have reported collecting records of additional individuals they believe were also wrongly arrested.

We will work tirelessly to ensure that people who were unlawfully arrested will be able to return to their families and communities as soon as possible, said Keren Zwick from the National Immigrant Justice Center.

Despite a message left for the Department of Homeland Security not receiving an immediate response, the consent decree—which had lapsed earlier this year—has been extended until February. The federal government has attempted to contest this extension in court. Originally established between immigrant rights advocates and federal authorities following a 2018 lawsuit against immigration sweeps, this agreement pertains to immigrants arrested in several states under the jurisdiction of the ICE field office in Chicago, including Illinois, Indiana, Kansas, Missouri, Kentucky, and Wisconsin.