West Virginia has decided to no longer hold U.S. Immigration and Customs Enforcement (ICE) detainees in its jails, a policy shift that follows a large-scale enforcement operation earlier this year, according to NPR.

The operation, dubbed “Operation Country Roads,” resulted in the arrest of 600 immigrants over a two-week period. Most of those arrested had no criminal records, NPR reported.

The state’s decision to stop housing ICE detainees came after the operation, which drew scrutiny over the scale of arrests and the lack of criminal histories among many of those detained. NPR’s report, which aired a look at West Virginia in the aftermath, noted the state’s jails would no longer participate in holding detainees for federal immigration authorities.

The report did not specify the exact date of the operation or the timeline of the state’s decision, nor did it name state officials who made the call. No official response from West Virginia or ICE was included in the source account.

The move marks a notable shift in the state’s cooperation with federal immigration enforcement, though the broader implications for ICE’s detention capacity in the region were not detailed in the report.