Gray wolves once freely roamed the United States until hunting nearly brought them into extinction by the 1940s. That is around the last time one of these animals was seen around the Grand Canyon in Arizona – until now, with photos emerging of a possible gray wolf in the area.

Photos of the gray wolf were taken by amateur photographers near Arizona’s Kaibab Plateau, according to the National Geographic. The region is north of the Grand Canyon National Park.

The wolf in the pictures is wearing a collar and, if not confirmed as a gray wolf, may actually be a “rarer subspecies” of Mexican gray wolf – “a wolf-dog hybrid,” an official with the U.S. Fish and Wildlife Service’s Southwest Region office told National Geographic. Another theory is that the collared animal may be one of the wolves reintroduced to the wild in the Northern Rocky Mountains in 1995. These animals are on the U.S. government’s endangered species list.

However, the photos suggest it’s not a Mexican wolf, which is typically smaller than the gray wolf. The only way to confirm which species it is definitely is to analyze the DNA in its feces, which the Fish and Wildlife Service is currently completing.

The gray wolf population has increased to 1,700 in the West after being limited to the upper Midwest for decades, leading the Fish and Wildlife Service to consider taking them off the Endangered Species List last year, according to the National Geographic.

The gray wolves spotted in Arizona may have traveled from Wyoming or another Rocky Mountain state into Utah and Arizona. The animals are known to travel long distances.