An aspiring politician and video game designer who faked his own beheading by Iraqi militants set off a short-lived media frenzy and an FBI investigation Saturday after media around the world began showing his homemade video of the gruesome hoax.

Benjamin Vanderford, 22, said he posted the 55-second clip, which shows a knife sawing against his neck, on an online file-sharing network in May.

It circulated in cyberspace before airing on Arab television.

Vanderford said he made the video as a way to draw attention to his campaign for a seat on the San Francisco Board of Supervisors. He filmed the footage at a friend's house, using fake blood. When his political aspirations waned, he decided to distribute the footage on Kazaa, which is used to trade millions of audio, video and software files daily, "to just make a statement on these type of videos and how easily they can be faked."

On the tape, aired Saturday on Arab television, Vanderford sits on a chair, his hands behind his back, rocking back and forth.

"We need to leave this country alone. We need to stop this occupation," he said on the video. "Everyone's going to be killed this way."

The tape then shows a hand with a knife cutting at the motionless man's neck, but it does not show any militants.

Vanderford said the file-sharing network provided a free and convenient distribution channel for the clip. His only challenge was making it look authentic.

"We had to make it more lower-quality to make it more realistic," he said.