NEW YORK (Reuters) – More than a dozen Muslim community leaders boycotted an interfaith breakfast organized by Mayor Michael Bloomberg on Friday to protest reported police surveillance of Muslim areas since the September 11, 2001, attacks.

In an open letter to Bloomberg, the leaders accused the mayor of ignoring concerns that the New York Police Department has been using racial profiling and violating civil rights in its anti-terrorism surveillance programs.

“We believe with heartfelt conviction that during times when a community’s rights are being flagrantly violated its leaders cannot in good conscience appear at a public gathering with the government official who is ultimately responsible and smile for the cameras as if all is well, when we know full well that it is not,” the letter said.

The letter cited a series of articles earlier this year by The Associated Press that alleged that police, at times in cooperation with the CIA, infiltrated New York mosques, Muslim bookshops and other Islamic businesses and institutions to gather intelligence without specific evidence of any criminal activity.

The letter was signed by 15 leaders of Muslim organizations based in New York City who said they were turning down their breakfast invitation, as well as the leaders of several dozen other faith organizations and civil rights groups.

The mayor’s office said 368 guests attended Friday’s breakfast, up from 315 people last year. The office said the guests included representatives of the Muslim community but did not have a specific number.

Bloomberg has defended the police department, which denies the accusations.

“Contrary to such assertions, the NYPD lawfully follows leads in terrorist-related investigations and does not engage in the kind of wholesale spying on communities that was falsely alleged,” police spokesman Paul Browne said in an e-mail.

Browne said “selective use” of undercover officers had thwarted several bombing attempts in New York City since the 2001 attacks by al Qaeda extremists.

In 2010, a Pakistani-born American man attempted to set off a car bomb in Times Square. Faisal Shahzad said when he pleaded guilty that Islamic extremists would continue to attack the United States.

Linda Sarsour, director of the Arab American Association of New York, said she and others boycotting the breakfast wanted an independent investigation into the NYPD’s surveillance methods.

“We’ve received no substantial proof that there has been no wrongdoing,” she said.

Almost three dozen members of the U.S. Congress signed a letter this month calling on the U.S. Department of Justice and the House Judiciary Committee to investigate whether the NYPD “has exercised authority beyond the scope of the law and in violation of the Constitution.”

Stu Loeser, a spokesman for the mayor, said the mayor’s office and the NYPD maintain “strong ties” with the city’s Muslim communities.

(Editing by Ellen Wulfhorst and Greg McCune)