At least two detainees taken into custody on April 19 have been freed on bail after pledging not to distribute illegal compact discs of underground music.
Western music is widely banned in Iran, and censors keep a close watch on the domestic arts scene.
Many Iranians, especially young people, find their way around the ban to listen to Western music.
Some unsanctioned Iranian acts have developed their own underground styles of rock, hip hop, and other music that authorities deem un-Islamic.
Same Old Tune
In December 2005, Iran's president ordered state media not to play "Western and decadent music." more
RFE/RL presents an excerpt from "Tehran Blues," an account of a generation growing up after Iran's Islamic Revolution by Radio Farda journalist Kaveh Basmenji. more