Hundreds of people took part in rival protests over plans for a mosque near the site of the 9/11 terror attacks.
Police kept the banner-waving groups apart, although there were no reports of violence between supporters and opponents of the scheme in New York.
Opponents chanted "No mosque, no way" as supporters responded with "Say no to racist fear".
Developers plan to convert an old building into a 13-storey Islamic community centre and mosque.
Feelings ran high during Sunday's protests in Manhattan, close to Ground Zero.
'Un-American' claimsThere were face-to-face confrontations as demonstrators shouted at each other across the barricades, the Associated Press reported.
Opponents want the mosque to be moved further from the site where more than 2,700 people were killed in the September 11 terror attacks. BBC News
