An environmental group is suing the Trump administration for repealing protections for wolves, bears and other predatory animals that live on Alaska’s national preserves.

The Center for Biological Diversity is challenging the constitutionality of the Congressional Review Act (CRA), which Congress used to pass legislation that Trump signed repealing the Department of Interior's Refuges Rule.

The rule prohibited practices in hunting predatory animals such as wolves, bears and other wildlife in Alaska’s national wildlife refuges. Hunters were banned from killing wolves and their pups in dens and gunning down grizzly bears at bait stations, trapping and killing black bears with steel-jaw leg-hold traps or wire snares, and killing brown and black bears from an aircraft.

The center is asking the court to declare CRA’s prohibition on future rulemaking unconstitutional and reinstate the rule.

“Wolf cubs shouldn’t be slaughtered in their dens on the very wildlife refuges that are meant to protect biological diversity,” Collette Adkins, an attorney and biologist at the center said in a statement.

“It’s outrageous that Trump and congressional Republicans used this unconstitutional law to promote the senseless slaughter of some of Alaska’s most iconic wildlife. They clearly don’t care about the critical role these amazing animals play in healthy ecosystems.”

The Center for Biological Diversity was also the first group to challenge Trump’s border wall. The group claimed in the lawsuit it filed with Rep. Raúl Graijalva (D-Ariz.) that the proposed wall along the southern boarder violates environmental laws.