King County sheriff's detectives are investigating possible animal cruelty at a farm near Enumclaw that apparently has attracted "a significant number of people" to have sex with animals, a sheriff's spokesman said Thursday. The investigation was launched this month after authorities discovered the July 2 death of a man who suffered internal bleeding after engaging in anal sex with a horse at the farm, Sgt. John Urquhart said.

Investigators have interviewed several people in connection with the case, which was brought to authorities' attention after the man was dropped off at a hospital for medical treatment. A surveillance camera picked up the license plate of the car, which led sheriff's detectives to the farm and other people involved, Urquhart said.

Bestiality is not illegal in Washington state.

"Just sex with an animal per se, you'd have to prove some sort of animal cruelty out of that and that's why we've got more investigating to do," Urquhart said.

"A significant number of people, we believe, have likely visited this farm," he said, declining to specify a number while the investigation continues.

The Humane Society of the United States intends to use the case during the next state legislative session as an example of why sex with animals should be outlawed in Washington, said Bob Reder, a Humane Society regional director in Seattle.