Police Infiltrate Protests, Videotapes Show - New York Times: "Undercover New York City police officers have conducted covert surveillance in the last 16 months of people protesting the Iraq war, bicycle riders taking part in mass rallies and even mourners at a street vigil for a cyclist killed in an accident, a series of videotapes show."

"The officers hoist protest signs. They hold flowers with mourners. They ride in bicycle events. At the vigil for the cyclist, an officer in biking gear wore a button that said, "I am a shameless agitator." She also carried a camera and videotaped the roughly 15 people present."

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"Beyond collecting information, some of the undercover officers or their associates are seen on the tape having influence on events. At a demonstration last year during the Republican National Convention, the sham arrest of a man secretly working with the police led to a bruising confrontation between officers in riot gear and bystanders."

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"Provided with images from the tape, the Police Department's chief spokesman, Paul J. Browne, did not dispute that they showed officers at work but said that disguised officers had always attended such gatherings - not to investigate political activities but to keep order and protect free speech."