Institute of Race Relations [UK], issued September 2, 2004. From the press release:

The Institute of Race Relations publishes today a catalogue that details how hundreds of Muslims have been arrested under terrorism powers before being released without charge; how the special powers granted by parliament to tackle terrorism are being deployed in other spheres, such as in routine criminal investigations or in the policing of immigration; how the media have become 'embedded' in a process that leads to the stigmatisation of Muslims as terrorists.

Read the full study. Reported in JURIST's Paper Chase here.