Fitr, a joyous holiday marking the end of the holy month of Ramadan, this year falls around Sept. 11. Muslim leaders fear that their gatherings for prayer and festivities could be misinterpreted by those unfamiliar with Islam as a celebration of the 2001 terrorist strikes. The Muslim Public Affairs Council, an advocacy group based in Los Angeles, is contacting law enforcement and the Justice Department civil rights division to alert them to the overlap. The Islamic Circle of North America, which organizes Muslim Family Days at the Six Flags amusement park in several cities around Eid Al-Fitr, this year planned nothing for Saturday, Sept. 11, because of the anniversary. A founder of Muslim Family Day, Tariq Amanullah, worked at the World Trade Center and was killed in the attacks. The Council on American-Islamic Relations, a Washington-based civil rights group, is urging mosques to review the group's security guidelines, including clearing brush where people could hide and installing surveillance cameras. “The issue I can sense brewing on hate sites on the Internet is, ‘These Muslims are celebrating on September 11',” said Ibrahim Hooper, national spokesman for CAIR. “It's getting really scary out there.” The exact date of Eid Al-Fitr this year is not yet known. In North America, the Eid could fall on Thursday, Sept. 9, Friday, Sept. 10, or Saturday, Sept. 11. Haroon Moghul, a New York Muslim leader who speaks regularly at mosques, said mosque leaders have been discussing Eid Al-Fitr for months. “When we realized that Ramadan would be ending around that time, a lot of people started sitting down together and saying, ‘How do we handle this in a way that's appropriate?”' said Moghul, executive director of Maydan Institute, a communications consulting company. Moghul said most New York Muslims likely won't celebrate the way they normally do, and noted that a significant number lost relatives when the World Trade Center was destroyed. Many imams in the city plan sermons on dealing with loss and grief. “It's a very painful day for everyone,” Moghul said. However, he and other American Muslim leaders don't want to make so many changes that they appear to be giving in to those who reject any Muslim observance in the United States. Some critics have said Muslims should move the date of the Eid.