Sheriff's deputies are investigating the death of a dog whose body was found last week by a walker in a Cuyamungué arroyo. The animal had a makeshift noose around its neck.

The exact cause of the death of the dog — an adult female pit bull, white with light gray spots — is not known. But suspicious wounds, coupled with how the dog was found, lead investigators to believe the dog was cruelly abused, said Maj. Ron Madrid of the Santa Fe County Sheriff's Department.

When found, the dog was attached to 4-foot-long metal pole by rope and the noose. In addition, cartridges from a high-powered weapon were found near the body. A necropsy is pending, Madrid said, and it's not known yet whether there's a connection between the empty casings and the wounds.

Still, investigators are actively pursuing the incident as an extreme cruelty case, with possible felony charges. The Attorney General's Animal Cruelty Task Force is offering a $5,000 reward for information leading to the arrest and conviction of those responsible.

Madrid said the makeshift pole and rope were similar to a "catchpole" used by animal-control officers faced with vicious dogs.

The dog's body was found around 3 p.m. on Christmas Eve in an arroyo at the end of County Road 89, about a mile west of U.S. 84/285 near the Buffalo Thunder exit. Jennifer Schwalenberg, an area resident, said she was taking her dogs out for their second walk that day along her routine path when the two German shepherds hit upon the body. The corpse hadn't been there on an earlier walk around 10 a.m.

The scene was so shocking, she said, that she found herself hyperventilating. She ran home for her cell phone and hiked back to take photos.

"It was horrifying," she said. "I'm sure that someone hanged or strangled that poor dog."

Schwalenberg contacted the Pojoaque Police Department on Christmas morning, and staff there contacted Santa Fe County Animal Control. Later that day, Schwalenberg met up with an animal-control officer and they traveled together to the site, where the officer documented the scene and took the dog's body.

Schwalenberg also contacted the Attorney General's Animal Cruelty Task Force, which agreed to offer the award and spread the word about the abuse. Monica Garcia, communications director with Animal Protection of New Mexico, the nonprofit animal-welfare group that runs the task force, said the group works closely with local law-enforcement agencies to help find perpetrators.

"This is a horrible crime, and we want to see it prosecuted," she said.

Schwalenberg said she has agreed to post reward fliers in her community and do everything she can to help find those responsible. She's lived in the neighborhood about a year, and said most of her neighbors are animal lovers with plenty of dogs. She's already gone door-to-door in her neighborhood, and no one was familiar with the dog. "Everyone was shocked," she said.

But Schwalenberg said residents have told her several animal cruelty incidents had taken place in the valley.

Although not well known, the arroyo can be accessed by motor vehicles, she said, and there are some spots where people target practice.

Passionate about animals, Schwalenberg said she had to cancel Christmas plans after she found the dog's body. "I just stayed home on Christmas Day and cried," she said.

Sheriff's deputies are asking anyone who has seen the dog, is missing the dog or saw a suspicious vehicle in the arroyo between 10 a.m. and 3 p.m. to call the investigations division at 986-2490. The Attorney General's Animal Cruelty Task Force hot line is 877-5HUMANE (877-548-6263). Callers may remain anonymous.

Contact Ben Swan at 986-3051, bswan@sfnewmexican.com.