Three self-described "swingers" from Arizona including a couple said to be in an open marriage have been accused of using Craigslist to look for a dog for the woman to have sex with, ABC 15 News reports.

Deputies arrested Shane Walker, 38, his wife Sarah Dae, 34, and Dae's reported lover Robert Aucker, 29, on the charge of conspiracy to commit bestiality, the Daily Mail reports.

The arrest was the end result of an undercover operation that went on for weeks as the three used Craigslist to correspond with someone who they believed to be the owner of a golden retriever, according to the paper.

In reality, the correspondent was an undercover deputy, according to CBS 5 News. The deputy exchanged a series of e-mails with the threesome and convinced them to drive to a location where he would meet them with the dog. When the party showed up, they were arrested.

Shane Walker and Sarah Dae told deputies at the Maricopa County Sheriff’s Office that they are "swingers" who engage in an "open" marriage and that Aucker, their third partner in crime, was a former lover of Dae's, the Tuscon Citizen reports.

According to deputies, Dae told Aucker that she had always dreamed of having sex with a dog.

Maricopa County Sheriff Joe Arpaio said the case is the third in the past year in which Craigslist has been used to facilitate planned acts of bestiality, which is illegal in Arizona.

"I remain extremely disappointed in the leadership at Craigslist.com for refusing to do what they can to stop this," Arpaio told CBS 5 News. "While they aren't doing anything to stop it, I will continue to enforce all animal cruelty laws."