DELAVAN, Wis. -- The Humane Society of the United States said it is hoping a reward will stimulate leads in the case of the 5-day-old alpaca found decapitated in Walworth County.

The animal-protection group is offering up to $2,500 for information leading to the arrest and conviction of those responsible. The Animal Defense Council has offered an additional $500.

Tana Ward found the alpaca missing last month from her farm near Delavan. She later found 17-pound Arianne beheaded in a pasture.

She said there were no marks that might have indicated a coyote killed it. She calls the whole incident sickening.

Authorities are still looking for suspects. Anyone with information is asked to call the Walworth County Sheriff's Department at 262-741-4400.