An internet hoax has resulted in an Oregon man being dispossessed of everything he owned - including his horse.

Robert Salisbury was minding his business in a national park when he received a call from a stranger asking whether he really intended to get rid of his horse - the animal appeared in such good condition.

Not only did he intend to keep the beast, Mr Salisbury told the caller, but he had no plans to get rid of any of his belongings. To what did he owe the call? An ad on a popular website had suggested he had been forced to leave home suddenly, and that all his belongings were free for the taking, came the reply.

Mr Salisbury, an independent contractor from Jacksonville, Oregon, hurried the 25 miles (40kms) home from Emigrant Lake, in Jackson County. On his way he passed a truck laden with ladders, a lawn mower, and weed killer - all of which he recognised as his own.

"I informed them I was the owner, but they refused to give the stuff back," Mr Salisbury said, adding that the thieves had waved a copy of an advertisement from Craigslist, the listings website, apparently authorising the seizure, in his face.

En route he passed other cars packed with his possessions, and arrived at his house to find 30 people rummaging through his barn and picking over goods on his front porch.

The trespassers - all wielding copies of the Craigslist ad - tried to brush off his attempts to get them to leave. "They honestly thought that because it appeared on the internet it was true," Salisbury told the Associated Press. "It boggles the mind."

Mr Salisbury called the Jacksonville police as well as the sheriff's deputies from Jackson County, but by the time they arrived, several more cars loaded with his possessions had fled.

The sole query about the ad, which first appeared on Craigslist on Saturday, was raised by Michelle Easley, another of the opportunists - but not before she had helped herself to Mr Salisbury's horse.

Ms Easle had read that Mr Salisbury's property had been declared "abandoned" by the sheriff's department. "I can't stand to see a horse suffer so I drove out there and got her," she said. "The horse didn't look abandoned. She is in good shape for being 32 years old."

Ms Easley said the situation seemed odd, so she left a note on Mr Salisbury's door explaining about the advert. When she saw a second listing similar to the first, she decided to ring to check they were legitimate.

"I feel bad because I was a part of it," Ms Easley said. "It felt right to call the police."

Detective Sergeant Colin Fagan, of Jackson County Sheriff's Department, praised Ms Easley for her honesty, but said anyone caught with Mr Salisbury's property could now face prosecution. An investigation into the source of the advert has begun, he said.

It is not the first time that Craigslist has been used to defraud a home owner.

In April last year, a house in Tacoma, Washington, was stripped of its contents after a hoax advert invited people to come and take what they wanted.

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