Strategy in Germany against a rise of far-right extremism is under the spotlight after revelations of a string of neo-Nazi murders.
A conference of ministers and experts has been held in Berlin after an underground cell went undetected for a decade, killing 10 people, mostly immigrants.
Past intelligence gathering related to neo-Nazi groups and the use of undercover agents have been criticised.
Green party justice expert Hans-Christian Ströbele said: “These undercover agents do not lead to anything. They don’t report anything. The undercover agents are mostly people who end up continuing their racist, extreme-right thinking.”
The neo-Nazi cell came to light after a woman surrendered to police. Two other alleged members were found dead and another has been arrested.
It is reported that police found video recordings in which the group admits to carrying out the murders.
Authorities estimate there are as many as 25,000 far-right extremists in Germany.