LANDER, Wyo. (AP) — The U.S. Fish and Wildlife Service has authorized killing four wolves after ranchers near Lander have had three verified livestock killings by the animals.

The U.S. Department of Agriculture's Wildlife Service has been using helicopters in the Wind River Mountains this week looking for the pack of wolves responsible for the killings.

Wyoming Ecological Services Deputy Field Supervisor Tyler Abbott says the pack believed to be responsible consists of seven adults and seven cubs. Two of the adult wolves were killed Friday and Wildlife Services is searching for two more.

Abbott says if the wolves continue to kill livestock in the area, he could order the extermination of the entire pack.