I've just caught the end of an important edition of File on 4 on the growth of violent extremism among the British far right. The show has now finished but is available on Listen Again http://www.bbc.co.uk/programmes/b006th08 .

Today's edition is a repeat of last Tuesday's broadcast, and it looks as though it will be taken down from Listen Again at 20-00 on Tuesday 22.09.

If you want to grab it, grab it now.