A report released by a group of human rights lawyers found that New York police officers often violated the rights of journalists covering Occupy Wall Street protests and arrested at least 18 of them, according to the Reporters Committee for Freedom of the Press. The Protest and Assembly Rights Project, the coalition of lawyers that authored the 200-age report, listed numerous incidents where reporters were obstructed, arrested or physically abused since the beginning of the Occupy movement in September.

The study also found that the NYPD conducted frequent surveillance during the demonstrations. The report said a “media blackout” during an eviction of protestors in Zuccotti Park on Nov. 15 was “the most egregious single example of police violation of the rights of the media to cover protests freely.” Relying on eight months’ worth of data collection and the testimony of journalists who were blocked from covering the eviction, the study noted that many reporters were forcibly removed from the scene and that at least 10 of them were arrested that day.