Opponents demand that the mosque be moved farther from the site where nearly 3,000 people were killed on Sept. 11, 2001. Ayling said, "They should put it in the Middle East," and added that he still vividly remembers watching television on 9/11 "and seeing people jumping from the towers, and ashes falling on my house."

On a nearby sidewalk, police chased away a group that unfurled a banner with images of beating, stoning and other torture they said was committed by those who followed Islamic law.

The mosque project is being led by Imam Feisal Abdul Rauf and his wife, Daisy Khan, who insist the center will promote moderate Islam. The dispute has sparked a national debate on religious freedom and American values and is becoming an issue on the campaign trail ahead of the midterm elections. Republicans have been critical of President Barack Obama's stance: He has said the Muslims have the right to build the center at the site but has not commented on whether he thinks they should.

At a pro-mosque rally staged a block away from opponents' demonstration, several hundred people chanted, "Muslims are welcome here! We say no to racist fear!"

Dr. Ali Akram, a Brooklyn physician, came with his three sons and an 11-year-old nephew waving an American flag in his hand. He noted that scores of Muslims were among those who died in the towers, and he called those who oppose the mosque "un-American."

"They teach their children about the freedom of religion in America — but they don't practice what they preach," Akram said.

Gila Barzvi, whose son, Guy Barzvi, was killed in the towers, stood with mosque opponents, clutching a large photo of her son with both hands.

"This is sacred ground and it's where my son was buried," the native Israeli from Queens said. She said the mosque would be "like a knife in our hearts."

She was joined by a close friend, Kobi Mor, who flew from San Francisco to participate in the rally.

If the mosque gets built, "we will bombard it," Mor said. He would not elaborate but added that he believes the project "will never happen."

The Sunday rallies coincided with an annual motorcycle ride by a group that raises money for Sept. 11 first responders.

Bikers rolled in from the two other Sept. 11 attack sites, Washington and Shanksville, Pa.

The imam behind the project is in the middle of a Mideast trip funded by the U.S. State Department that is intended to promote religious tolerance. He has discussed efforts to combat extremism, but has avoided any comments on the rancor over the planned Islamic center.

Rauf told the Al Wasat newspaper in Bahrain that the freedoms enshrined by the U.S. Constitution also reflect true Muslim values. A portion of the interview — to be published Monday — was seen Sunday by The Associated Press.