The US Secret Service is trying to identify the people who launched an online poll at Facebook asking whether US President Barack Obama should be assassinated.

Facebook on Monday shot down the user-generated poll, which was titled "Should Obama be killed?" and offered answer choices of yes, no, maybe, and "If he cuts my health care."

"Once we found out about it, we worked with Facebook to have it removed," Secret Service spokesman Malcolm Wiley told AFP.

"We are certainly investigating; just like we would with any threat case."

More than 750 Facebook users had reportedly cast votes by the time the poll was yanked from the wildly popular online social networking community.

"This is sick and sad," a Facebook user with the screen name Cocoa Fly said in a posting as the poll fuelled passionate online exchanges at the website.

"All of this anti-Obama rage is pure racism."

http://www.theage.com.au/technology/technology-news/facebook-forced-to-yank-obama-kill-poll-20090929-g9x0.html