A woman driver who alerted the police helicopter after she found him lying in the road on Saturday has spoken of her fright.
A female driver, who asked not to be named, spotted the man on the side of the road near Ratford Bridge Farm shortly before 1am, lying in what was thought to be a pool of blood.
She said: "I was driving along when I saw this man on the side of the road.
"I started beeping my horn to get his attention because I thought he might have been unconscious and he got up and walked over to my car.
"It was really horrible because he claimed he did not know who he was.
"When I found him he had blood coming from his ear and had been sick down himself - I was absolutely scared stiff.
"He wanted to get in and he asked if he could put his bags in my car - it was really scary."
The woman then drove to the A4 where she could get a telephone signal, and called the police at 12.54am.
"I dialled 999 and after that a police van passed," she said. "I flagged it down and showed them where the man was but he had gone.
"They said I did the right thing in calling them because he had tried to get in my car.
"I was a bit panicky until the police came but I was ok when I got home.
"I just hope the person was alright - he had no idea who he was."
The police helicopter circled a two-mile radius above the scene, but the man was not found.
A spokesman for the Wiltshire Police said: "A woman was driving down the road and saw this man lying near a bike in what she thought was a pool of blood.
"She drove down the road and flagged an officer down to report it, but it turned out not to be blood but sick. "When paramedics arrived they found a man on a bike, but it was a different guy.
"The helicopter was called out but there was nobody there."
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