As well as anyone, Sybille Geissler knows the threats from Austria's far-right extremists, who in recent weeks have likened migrants to rats and blithely defended campaign material that evokes Nazi propaganda.

For more than 12 years, she has led the anti-extremism unit of the domestic intelligence service, and recently testified in a parliamentary inquiry into whether the far-right was trying to undermine her agency.

Her biggest challenge these days, her testimony suggests, is that the far-right is part of her own government.

Shortly after the far-right Freedom Party joined the government 17 months ago, taking over the powerful Interior Ministry,