BILLINGS, Mont. (AP) — Federal wildlife officials have rejected a petition from advocates who sought to reclassify gray wolves as a threatened species in most of the U.S.

Gray wolves across most of the Lower 48 are classified as endangered, which is more protective than a threatened designation. Advocates hoped a change to threatened would pre-empt intervention from members of Congress who want to lift federal protections altogether.

The U.S. Fish and Wildlife Service said in a Tuesday notice that the petitioners didn’t sufficiently back up their claims that wolves remain at risk due to disease and other factors.

The petition was filed in January by more than a dozen groups including The Center for Biological Diversity.

Wolves in Minnesota already are listed as threatened. The animals are not federally protected in the Northern Rockies.

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