"[The] investigations are a strong hint to people running other extreme-right internet radio stations that dissemination of songs with extreme-right wing and xenophobic lyrics, even on the internet, will be pursued," said BKA head Joerg Ziercke.
He said they had noticed a growing trend among far-right groups to use music to recruit young people.
Last month, the BKA said that over the past decade the number of people with the potential to carry out far-right violence in Germany had doubled to around 9,000.
The BBC's Stephen Evans in Berlin says the arrests come during an intense debate in Germany over immigration, particularly from Muslim countries.
http://www.bbc.co.uk/news/world-europe-11689141
Note: Update post,3 November 2010 Last updated at 21:58 GMT