Media Matters for America has the details.

See also “Anti-Park 51 rally attendees echo Fox News misinformation and right-wing Islamophobia”, by Ben Armbruster at Think Progress, which features the following video in which participants at the SIOA 9/11 demonstration parrot the lies and distortions spread by Fox News and the rest of the anti-Muslim right (it ends with some sensitive and rational comments by supporters Park51).